Diane/Plot

Introduction arc
Diane's wanted poster is displayed on a board within the Boar Hat.

Forest of White Dreams arc
The defeated Prankster Imps retreat to a sleeping Diane, inadvertently leading Meliodas, Elizabeth and Hawk to her. Diane wakes immediately upon hearing the Imps apologies for allowing a Holy Knight to come through, since they believed Meliodas to be one, and then instantly grabs Meliodas with one hand. After realizing his identity, however, she cuddles her captain, and when Elizabeth introduces herself to be traveling with him, throws a tantrum. Meliodas, after calming Diane, begins a discussion on the day the Deadly Sins were framed for the Great Holy Knight Zaratras's murder. However, he also reveals that he has almost no memories of that day, and then narrates the only memories he has, which end with someone apologizing to him, addressing him as "captain".

This leads Elizabeth to speculate the existence of a traitor, and Diane, to declare that she will help Meliodas no matter the foe. Few moments later, Hawk notices a gigantic thundercloud in the sky, from which a lightning bolt descends and immobilizes all of them, with Elizabeth introducing the assailant Holy Knight as Gilthunder. After he leads her away, ending her interruption, he expresses his desire to fight Meliodas, and reveals his connection to Zaratras, the Great Holy Knight. Before the battle, Meliodas and Diane easily break his immobilization themselves, and the former instructs the latter not to interfere. Diane quietly observes the battle, watching worriedly when Meliodas is gravely slashed. When Gilthunder continues attacking Meliodas and refuses to end the battle, Diane grabs him, and ignoring his attempts to escape her grip, flings him from the forest. Sometime afterward, Diane leaves along with her captain, Hawk, and Elizabeth. Meliodas decides to head for Baste Dungeon, where Ban, the Fox's Sin of Greed is imprisoned, leading Elizabeth to object, citing his grave wound at Gilthunder's hands. Though he affirms her that it is not major, he soon collapses.

Baste Dungeon arc
Diane, Elizabeth and Hawk then travel to a town near the Baste, named Dalmary, in order to have the severely injured Meliodas treated by a doctor named Dana. As she sits next to Dana's house, she is watched with discriminatory wariness due to being a giant. Not long until Diane decides to head to the dungeon herself, retorting that Elizabeth would only be a hindrance when the princess asks to join. Elizabeth replies her desire to be of use, and that Meliodas was taking on "more than he can handle". This angers Diane, her saying that Meliodas was not doing so for the princess alone, and that such was his usual personality. She continues, narrating the episode of her and her captain's first meeting, and how he treated her at that time. As Elizabeth declares her wishes of wanting to have strength, Diane declares her own of wanting to be small. Abruptly, Hawk notices a huge swarm of poisonous insects flying toward Dalmary.

Although initially plagued by her fear of insects, Diane overcomes it and quickly kills them by raising huge pillars from the earth, much to the surprise of Friesia, the assailant. While Elizabeth and Hawk awe at Diane's ability, and she leaps out of Dalmary and, handing Elizabeth the duty of taking care of Meliodas, starts running toward the Baste Dungeon. Diane, later on, encounters Meliodas, Elizabeth and Hawk when the three are walking to the Baste Dungeon. She mysteriously seems to have no recollection of having defeated Friesia and having left for the dungeon previously.

Diane tries to recollect, when she suddenly finds Meliodas and Elizabeth to have vanished, and Ruin to be standing in their place. When the Holy Knight claims to have already captured them, she attacks him, but is soon revealed to be under an illusion that deludes her into seeing Ruin in Meliodas' place; she thus attacks Meliodas while believing that she is attacking the Holy Knight.



Meliodas, immediately flees along with Elizabeth, and Hawk, and upon finding two civilians walking nearby, takes them along. As the five hide, Meliodas also falls under Ruin's hypnosis. Seeing Ruin in Diane's place, he, thinking he is attacking Ruin, jumps up, rolls and slashes from above, with Diane blocking it with her fist and responding by raising sharp pillars from the earth toward him, which he in response deflects. Diane and Meliodas' battle continues, uninterrupted, and only stops when Elizabeth manages to remove the source of Ruin's illusions - his staff's bell.

Later, during the aftermath of Meliodas and Ruin's battle that ends in the latter's defeat, Diane quickly defeats Friesia with a punch that utterly crushes the Holy Knight. Walking towards the heavily injured Elizabeth, Diane removes her giant backpack, intending to place her inside and take her to the town for treatment. Elizabeth, however, requests to be taken inside Baste, to which Diane complies. The second, and older shepherd is revealed to be a soldier who was ordered to act as a civilian. When he refuses to reveal Ban's location due to fear of his superiors, Diane threatens him while holding Friesia's defeated body. Inside, the group encounters Dr. Dana's daughter Sennett and Ban. As Meliodas and Ban greet each other, and arm wrestle, thus destroying the entirety of Baste, Diane simply watches as though this was a common occurrence. The group, along with Sennett and the other villagers, return to Dalmary where Diane looks after Elizabeth.

At night, during the party, Ban is formally introduced to Elizabeth; Diane has to stand while eating due to her size. During the party, Elizabeth expresses her joy, but states that the events in Baste have reminded her all the more about the Holy Knights' frightening abilities. Diane replies that while she is not interested in human kingdoms, she has no qualms with fighting for Elizabeth, since she was "really cool" that day, and did have powers: the power to move her and Meliodas' hearts. Diane also asks Elizabeth whether she could henceforth address her as merely "Elizabeth", instead of "princess", and then tells the young lady to address her as just "Diane".

Capital of the Dead arc
Diane and the others left Dalmary Town to travel on the road again to find the other Sins. Elizabeth apologizes to her for making them wait when she needed to heal but Diane said she shouldn't worry too much. As Meliodas was about to say where they should be going, they stumbled upon a suspicious group Holy Knight's who demanded to know where they were going, noticing Hawk Mama and Diane, a giant. Meliodas came out and told them that they were a traveling bar, and that Diane and Elizabeth were the attractive waitresses. The lie was working, until Diane hugged Meliodas in happiness at being called attractive and accidentally referred to him as "Captain."

When the apprentice Holy Knight was about to attack a Black Hound attacked, 'devouring' them. Meliodas scared it away by using his power, and they continued their path. Meliodas told them that they are going to the Capital of the Dead to find King. When they get to a village next to the Capital of the Dead, they decide to scavenge information on how to find King and how to get to the Capital. Meliodas appointed Diane as a poster girl and Ban as a chef. Diane attempted to reel in customers, but failed as the village was isolated. The Sins then realize that Ban has disappeared and decide to go out and find him. When they find Ban, he is fighting with someone. Meliodas bumps Ban on the head and instructs him to get back to work. He and Diane then see Ban's opponent, and recognize him as King, the Grizzly Sin. Diane becomes happy and smiles at him, saying that she was happy they had found him. In response, King said nothing and floated away in the opposite direction. Diane and the others then go back to the Boar Hat, and Ban serves food to a local girl named Ellen and her brother Luigi.

They group acquired information from the two siblings on how to get to the Capital of the Dead, and were told that King had asked them previously as well. As the spoke, Diane wondered what had caused King to react in such a cold way. As they wander the village, they come across the entrance to the Capital. They are surrounded by small, light pink flowers that swirl around them until they are transported to the Capital. Ban separates from the group to find something and King follows after him. As they walk around, a Holy Knight, Guila appears, having gained access by partially killing herself. Meliodas senses how dangerous she is and orders Elizabeth and Hawk to run away to safety. Guila launches an attack that sends the two Sins flying, and Meliodas manages to catch Diane before she was impaled by a sharp crystal.

Guila then comments that the capabilities of the Giant Clan and Diane's ability, "Creation", are not very impressive. As a response, Diane demonstrates her abilities by trapping Guila using her Sand Whirl. This fails, and Guila easily frees herself with a blast from the tip of her rapier. She forces Diane back with another explosion, and Diane attempts to crush her, but is blasted again as Guila dodges it. Ban returns and attempts to battle Guila using Snatch, but she reacts by using her power Explosion. The rest try to fight Guila together, but she is too powerful. Guila launches another explosion, but Diane uses her body to shelter Meliodas, leaving Ban out to be impacted by the attack.

Diane blocks all of Guila's attacks, resulting in her not wanting to move do to her injuries. King then appears to help them. Guila sends multiple attacks towards them but King easily blocks them all with his Sacred Treasure Chastiefol. Guila comments on his spear power insists on going four-on-one with the Sins. King refuses, saying he wishes to go one-on-one and would rather let the other Sins rest. Guila is caught off-guard by King's powerful magic, and is almost defeated. She attempts to give a final blow to King as he turns around, but is sent back to the living world by the force of Meliodas' Full Counter. The Sins bodies began disappearing too, and they slowly return to the living world as the Capital rejects them. When they get back, they find that Guila was still in a trance of near death. King insists on petrifying her, but Meliodas offers to do something to her before they leave.

King was worried that Diane might still be injured from before and tells her to rest, but Ban laughs and tells him that she had been faking it the whole time in an attempt to get attention from the captain. King defends her and claims that Diane wouldn't do a thing like that, but unnoticed by King, Diane makes a face that suggests she was faking it. Elizabeth comments on how strong King was, which he responds by saying that any of the Sins could've beaten her with ease if they were wielding their Sacred Treasures. King is disappointed as he finds out that the other Sins no longer have them and comments on their carelessness. Diane had lost hers somehow. King chastised Meliodas and Ban for not having them, but didn't yell at Diane as she put on a puppy-eyed look. He said that her losing it wasn't her fault, and that it couldn't be helped.

Vaizel Fight Festival arc
The next day, Diane is left behind with the Boar Hat while King, Meliodas, Diane and Hawk travel to Byron, since she is easily noticeable. The next day, Diane throws a tantrum at similarly not being able to accompany them into Vaizel. Elizabeth insists on staying with Diane, and they head to look for ingredients in the nearby forest after the other Sins leave. In the woods, Elizabeth finds a mushroom-like monster, which Diane, tries to grab, considering it an ingredient. The creature, much to Diane and Elizabeth's shock, releases spores that shrink both of them. Diane wears Elizabeth's clothes and jewelry, in order for them to not be lost, and then, wanting to surprise Meliodas, enters the Vaizel Fight Festival under the name of "Matrona", with the shrunken Elizabeth hiding in the shrunken Diane's bosom.

As Matrona
The shrunken Diane is first seen during the preliminary of the fighting festival, in which, she quickly and easily defeats many of the other contenders, and advances. Afterwards, she is assigned to fight against Griamore. After she, and her opponent, have entered the ring, Love Helm, the referee, requests her to remove her cape to confirm whether she has any weapons. She does so, revealing her incredible identicalness to Elizabeth. Griamore, dismissing Veronica's worries about "Matrona" being Elizabeth, readies himself. As the battle begins, Diane immediately attacks Griamore, all of which are, negated by the Holy Knight's ability, Wall. While Diane is being pushed outside the ring, Griamore states his intentions of humiliating Meliodas next. This enrages Diane, who proceeds to destroy Griamore's ability, and then defeats him, with a single punch. This greatly surprises both Veronica and Howzer the impact causes Diane's hat to fall off.

As "Matrona" is declared the victor, her facial appearance is now revealed to be identical to Diane's, and she skips towards Meliodas, Ban and King, believing that her secret has been revealed, but is only greeted with Meliodas' question as to her identity. Irritated, Diane punches him storms off, turning back when King asks her about her body, and Elizabeth's whereabouts. Diane replies that "she" is right there, with an expression of Elizabeth's. After Elizabeth appears in Diane's bosom, Diane explains how she and the princess shrunk, upon hearing which King recognizes the creature that did so. Diane jumps over to Meliodas, merrily expressing her elation at being held by him. She then asks Meliodas to grope her as he gropes Elizabeth. When Diane becomes upset at his refusal, Meliodas comforts her, explaining that he cannot act so to an important individual as her.

Diane then watches Cain Barzad and Old Fart (King's disguise name) fight, and then, Meliodas and Ban's battle. During the latter's battle, when Meliodas appears to be weakening, Diane wonders the reason, in which King answers as being due to Ban's ability, Snatch. After Ban completely steals all of Meliodas' abilities, and stands over him, Diane yells at Ban to not further harm Meliodas. Meliodas himself refuses to give up, leading Diane to theorize that Meliodas is baiting Ban to delivering a powerful punch, and will then reflect it with Full Counter. King, however, explains of Full Counter's limits, that doing so would be impossible. After Meliodas somehow wins, Diane tells King that in midst of Ban's attack's aftermath, Meliodas' eyes suddenly became black, and that he had a strange symbol on his forehead; she states that Meliodas then crushed Ban's hand, then goes on to defeat him. Diane states that she has seen this before, and that it makes her feel uneasy. When the next battle is declared to be between "Matrona" and Howzer, Diane hurriedly hands Meliodas the shrunken Elizabeth and the princess' pendant, before leaving for the battle.

As the battle begins, Howzer informs Diane that her chest button was undone. After the minor interruption, he charges, attacking with a small tornado around his arms. Diane, while dodging, comments on the attack's danger. After much evading, Howzer, finally, proceeds to deal the final attack, but finds "Matrona" to be easily stopping him. Diane pushes him away with a single slap, adding that she had earlier commented his ability to be dangerous only because she did not want her clothes to be torn. Finally able to unleash his powers, Howzer uses another technique, which causes Diane no damage again, leading to Howzer's confirmation that she is a Deadly Sin. Not giving up, he then forms a gigantic twister, large enough to cover the entire ring. Despite his confidence of his victory, Diane increases her body's mass, and uses the increased gravitational force to defeat Howzer from above. Howzer then acknowledges his defeat and states that he is honored to have been fought seriously by Deadly Sin; he then confirms Diane's identity when King addresses her by her name.

During Cain and Meliodas' battle, when Diane wonders about the fighters' relationship, Ban instructs her to stop, citing the third law of the Deadly Sins. After the battle, the final battle of the Fight Festival, between Meliodas and Matrona is announced. Just as Diane suggests to merely act as if they are fighting, three women cheer Meliodas in an erotic manner. Diane, enraged, assumes that Meliodas' obliviousness is because he has relations with so many women that he doesn't recognize them all, and, enraged, punches him to the ground.

Diane refuses to believe Meliodas' claims that it was a misunderstanding, and exchanges a barrage of very powerful and relentless attacks. As Meliodas attacks, he wonders why she is as powerful even after shrinking. He then jumps, and tries to land the finishing blow. His punch is, however, stopped by Diane with one of her own. As she pushes Meliodas back, her size gradually returns to normal. Diane continues attacking Meliodas, but he repeatedly evades her by slipping through the cracks on the ring. When the audience expresses its dislike at the low seriousness of the battle, Meliodas declares his identity, and that he will now be taking over Vaizel. Ban and King also enter the ring, with Meliodas continuing that he will give the town a chance: he orders them all to leave Vaizel, lest be massacred by the Sins. A few moments later, several gigantic flares rain down on the town. The attackers are shown to be Guila, Jericho, and another Holy Knight; the citizens, believing that the Holy Knights have come to save them, cheer, but are quickly threatened into fleeing.

As Diane
Elizabeth then understands the Sins' actions: they acted so in order to have the civilians evacuate. Meliodas notes that their opponents are much more powerful than earlier, and instructs King, Diane and Ban to separate. Diane, acting upon her instruction, then reaches the area where Gideon was kept, but finds the weapon to not be there. As she wonders on her course of action, Howzer walks up from behind, declaring that he will be arresting her, since he believes that they are plotting to take over the kingdom again. Diane then notices a civilian trapped under the debris and runs to help, just as Marmas walks up to the two, and proceeds to use a technique that multiples gravity around Diane by ten times. Diane throws the civilian to Howzer, as the earth collapses due to her increased weight.

After being dropped into the pit, Hawk Mama appears before Howzer and Marmas, carrying Diane's original clothes and tosses them into the large opening. After Helbram successfully defeats the rampaging Meliodas with a portion Hendrickson's power, Diane appears from the hole, smashing Marmas at the same time. As Diane climbs out of the pit, Diane asks Howzer if he is surprised of her true size, but Howzer told her he was not and was glad that she's okay. Diane then ask Howzer to take Marmas and the old man and run away, which surprised Howzer. Diane then playfully asked if Howzer still wanted to capture her, but Howzer tells her that the Kingdom will be after them after they find out about Vaizel. Howzer at this point begins to grow feelings for Diane, realizing her true nature. Diane later finds her sacred treasure Gideon and heads towards where Meliodas and Helbram are fighting where she saved Meliodas before Helbram could take him away. Diane saw the defeated Meliodas, and she went into a deep thought until she went furious at Helbram for what he had done to Meliodas and uses Mother Catastrophe to crash the area around her.

Helbram started to retreat due to Diane's great power and Hendrickson ordered him to escape, but Diane then forms a giant floating mountain and crushes Vaizel, possibly killing Helbram. Later when the smoke cleared up, Diane looked at the injured Meliodas which made him wake up and saw Diane, Diane then got so happy that she cuddled him. As Elizabeth was running toward the injured Meliodas, he was then punched by Ban who was angry at him for cutting him in half which made Diane upset at Ban. Diane later picked up Meliodas and was upset at him because he asked Elizabeth if she was alright, then he's happy which made Diane upset because Meliodas is not worried about her, he tried to calm her down by saying that she is always fine in which she replied she's not fine at all. Later, Diane thanked Hawk Mother for getting her clothes and headed with the rest to a new location to find the other Deadly Sins or the next Sacred Treasure.

Armor Giant arc
After the Boar Hat stopped at an unknown location, Diane found and heard Elizabeth saying she will return the kingdom back to the way it was. Diane told her that she shouldn't worry about it, and she is free to use their powers since they are comrades. Diane and Elizabeth later met up with Ban and King who went to see Meliodas who were shocked to see the mountain sliced in half that was caused by Meliodas. Later, a group of kids who are role playing as the Deadly Sins, found the Boar Hat and started questioning them, Diane, who was hiding behind, thought everyone came back, and appears right in front of the kids who were shocked to see a giant, thinking that she's going to eat them which got her angry, saying she doesn't eat people.

After all things cleared up, Diane ends up playing with the kids, in joy. Pelliot then told them about a Mountain God who lives in Ordan mountain. Then they were later informed by a villager that a group of Holy Knights the Dawn Roar are up in the mountains hearing this the kids headed towards the mountain to find them. The Deadly Sins then hear from an injured knight that an "Armor Giant" was at the mountain and beaten them all with ease. Meliodas then realize it was Gowther. Once Meliodas explains the situation to Diane, the latter then realize that Gowther was pretty big and wears armor. Diane asks if she can go along, but Meliodas refuses and orders her to stay behind and protect the sick Elizabeth.

Diane was surprised but happily agrees to stay behind. Diane was later informed by Hawk that Cain Barzad came to the Boar Hat while he called him names which Diane told the latter it was rude. When Cain ran out of the bar to see what's happening in the forest, Cain was surprised to see a giant in the area and wonders how she knows him. The Deadly Sins then return with Gowther where Diane and Elizabeth were surprised to see Gowther without his armor, but all of them end up celebrating. Gowther later used his power Invasion on Diane and Ban which he revealed that Diane was lying about her true height which is 30 feet tall not 29 to much to her embarrassment, smashed him to the ground repeatedly. When Gowther revealed that Elizabeth is in love and it could be Meliodas, King and Ban try to calm Diane down but were surprised to see her pass out due to drinking.

Kingdom Infiltration arc
Diane was chatting with Hawk Mama about what she eats which Diane doesn't understand and got mad when Meliodas needed comfort from Elizabeth as she breaks the window. As Meliodas explain his reason to head to Liones and get his sword back, Diane wonders why the Demons aren't released yet, Meliodas reveals that there are more pieces to the Coffin of Eternal Darkness since the seal is incredibly strong and there would have been a sign. Hawk asks why the Holy Knights are after Elizabeth as well, until a mysterious Holy Knight appears and reveal that Elizabeth is the last key needed to revive the Demon Clan. The mysterious Holy Knight took Elizabeth in which Meliodas orders Diane to toss him to Liones along with Ban and Gowther. Diane grabs hold of the Deadly Sins as she told Meliodas to bring back Elizabeth, and toss them toward Liones in full speed.

Diane and King start traveling towards Liones by foot along with Hawk Mama, planning to help out as they are the only one's possessing their Sacred Treasure. She asks King if he had ever seen Meliodas so angry before and King replies that it was his first time seeing him like that. Diane starts wondering if she washes the one kidnapped instead of Elizabeth, would Meliodas be as angry as he did with Elizabeth. King tells her that Meliodas will definitely go to save her since they are important friends, and states that he himself will definitely come for her. Diane tells him that she is happy, but King wonders if she actually cheered up. He soon realizes that they should hurry and summon his pet, Oslo. He reveals its ability of teleportation and tells Diane to enter Oslo's mouth. They eventually realize that she is too big for the Black Hound's mouth, so Diane tells him to push her in. King blushes at the sight of her rear end and quickly orders Oslo to open his mouth wider.

Diane arrives at Hendrickson's Magical Research Facility, and is immediately questioned by Dreyfus, asking for her goal. Without hesitating, the Deadly Sin demands to have Elizabeth returned, leaving the Great Holy Knight only confused. Howzer becomes more and more nervous, and Jericho decides to deliver the first attack. Diane straightaway swings Gideon, destroying part of the building and blasting Jericho away. Gilthunder then proceeds to begin attacking, and under Dreyfus' commands, Howzer reluctantly enters the battle as well. However, despite using a combined technique, Diane was able to fend off the technique by using Ground Gladius. When she attempts to unleash Ground Gladius for a second time, Dreyfus easily blocks it and uses his ability Break to pierce through her chest.

After being heavily damaged by Dreyfus' Break ability, Diane briefly collapses on the floor whilst coughing out blood. Helbram returns to the group of Holy Knights after evading Diane's Ground Gladius by sacrificing some of his subordinates. Diane attempts to move again, but Dreyfus uses Pierce to damages her leg, and is sent flying away to the city by the Great Holy Knight's technique, Pulverize. When she crashes into the buildings and astonishes the civilians, Dreyfus proceeds to use an Incantation Orb to project his voice throughout the kingdom, stating that the Seven Deadly Sins have infiltrated Liones to stage an attack. The civilians begin attacking and throwing rocks at the confused Diane who tries to explain what's happening to the people. Helbram proceeds to destroy more buildings to frame Diane as a villain. Guila notices the trickery and demands Helbram to explain his actions, which he replies by saying that the Sins will play the role of villains so that the Holy Knights can be heroes. Suddenly, Zeal notices Guila, when a building starts collapsing above. Without thinking, Diane leaps and dives forward to protect Zeal, causing herself to be completely immobilized by the collapsed building. As the Holy Knights prepare to kill her, Howzer and Guila steps in to protect Diane.

As Guila and Howzer initiated a suicidal battle against their former comrades, Diane tells Zeal to stay down while she protects him from the destruction caused by the two rogue Holy Knights' Combined Technique: Bomb Cyclone. As Dreyfus and Gilthunder fled the battle field due to Dreyfus' injury. Helbram was left behind to finish them off which he called upon Call of Inferno which nearly killed Howzer and Guila until Diane stood up and smash Helbram before he could do anymore damage. Diane gave Zeal back to Guila and told them to get to safety, but Howzer refuses, saying that she should worry about herself more than others for once in which she smiled. But Helbram raised up and striked Diane with Killer Iceberg that heavily damaged Diane even further and put her to a near death situation. Helbram unleashes a barrage of ice attacks to finish her off when suddenly King appears and saves Diane. As King tries to find the one who injured Diane, Diane told King it wasn't Guila or Howzer as they are the one trying to protect her until she passed out.

As King protected her from Helbram roots attack, Diane woke up for a moment and says that she remembers this smell and says King's true name, Harlequin as she shed tears. After Helbram was killed by King, King flew towards the injured Diane and apologized to her for getting her in trouble, but Diane instead thanks him for saving her. King told Diane to leave everything to him, but Diane then said Harlequin which surprise King until Diane said that the name sounds nostalgic to her, but doesn't know why. King smiles and said it could have just been a dream. Diane later starts forcefully getting up while King tries to convince her to rest due to her injuries, but Diane refuses as Elizabeth needs to be saved and said that he doesn't need to worry because he already healed her of her wounds. While the others were trying to get Dreyfus on their side to save Elizabeth, Diane told Dreyfus she did not care if Dreyfus hurt her, but wanted to save Elizabeth as she was an important friend to her. As everyone got ready, they headed out to Hendrickson's location to save Elizabeth.

While on their way to save Elizabeth, Diane and the Sins feel a large amount of power exerted with very strong force in a nearby battle. After Gowther explains that Meliodas is fighting three Great Holy Knights, Diane begs King to go and help Meliodas, but King refuses as he wants to remain near Diane since she is still injured and knows that Meliodas is fine on his own. As everyone senses Gilthunder's full power, King realizes the fighting has stopped. Diane screams, thinking that Meliodas was killed, but Gilthunder, Margaret and Meliodas show up, revealed to be fine. Diane begins to cry and holds Meliodas, which Meliodas ignores and tells the group that they need to rescue Elizabeth. The group heads to the castle to rescue Bartra Liones and Elizabeth, but are teleported to a forest Vivian. Fortunately, they are sent back to Liones by a mysterious cloaked figure, who is soon revealed to be Merlin of the Seven Deadly Sins. After Merlin freed Elizabeth and Bartra. Elizabeth was worried over Diane's wounds when Diane revealed that she was saved by King Elizabeth felt glad that she was fine. Meliodas pointed out that they have defeated Hendrickson and freed the king, and ask Dreyfus what would he do now. As Dreyfus admitted defeated and was crying to know Griamore is alive, Meliodas happily declare that everything was fixed. However, after Merlin, Arthur and Bartra left to treat the kings wound, the castle was attacked by Hendrickson and awakened all the New Generation's demon blood.

As Jericho transforms into Demon and was about to kill the slowly transforming Guila and her brother Gustaf, Gowther along with Diane appeared and stopped Jericho from killing. Gowther used Invasion on Jericho and Guila to try to keep them calm. Diane was shocked and disgusted with Hendrickson who revealed that he used Enslavement of the Dead to revive Helbram and used him as a slave to fight off King. Seeing Elizabeth taken away by Hendrickson, Diane pleads her friend not to go while distracted it allowed Jericho to strike back and injure Diane again. As Diane was fighting off Jericho, she over heard Jericho saying that she want to be stronger than her brother which made Diane believe that Jericho is still alive inside, but doesn't know what to do. As Diane refuses to kill Jericho, Ban appeared and removed a strange "plant" from Jericho which cured her and returned back to normal. Diane was amazed at Ban's skill while she told Ban and King to go and cure the Hybrid Demon while Diane and the others go to save Elizabeth and help Meliodas.

Diane appeared at Merlin's Old Castle while destroying Hendrickson's severed arm while at the same time, saved Hawk and the bleeding Elizabeth which Diane claims that she will not forgive Hendrickson for what he did to Elizabeth. Later, Diane and the remaining Deadly Sins appeared to face Hendrickson in a final battle. As Hendrickson taunts the Deadly Sins for being out numbered due to the New Generation transforming into Demons, Meliodas points out that he should check again. Hendrickson senses that all the New Generations were stopped as they return to normal due to Ban and King's help while the other Holy Knight are currently surrounding the ruin castle. Hendrickson, however, was joyful to admit that the situation became more interesting and wondered how the Deadly Sins defeated the New Generation so fast, but admitted that the Sins can't defeat him. As the battle went with the Deadly Sins working together to fight against Hendrickson, the latter admits that he is invisible due to the demonic power, but when Diane traps him with Double Hammer, Meliodas explains to Hendrickson that demonic powers can heal wounds, but if he is not immortal or something, it would have been pointless as the damage would still remain. Hendrickson then smashes Ban into a wall where he found the demon corpse and returns to Hendrickson, questioning him on where he found it and why does he have it. Then the wall breaks down to reveal the demon which shocks the Deadly Sins.

Diane was shock and disgusted by the demon, but when Ban slam Hendrickson into the floor, Diane was left behind due to her size while the other Deadly Sins follow Hendrickson. When Hendrickson took the Gray Demon blood, Diane along with the other Deadly Sins were blasted out of Merlin's Old Castle, while passing out. Diane, however, was awake and used Rising Meteor on Hendrickson, sending him up towards the sky because of the rising ground. Diane told King to finish him which King did by almost using Form Eight until Hendrickson used Dark Nebula which easily defeated King and Diane. Diane watches in tears as Hawk died while protecting Elizabeth and Meliodas. When Elizabeth unlocks her hidden power and healed everyone, Meliodas thought of a plan and ask Gowther to use his ability to spread the message, but King was in tears, trying to reveal to Meliodas that Gowther was killed as his head was chopped off, but to Diane and King's horror and shock, Gowther was fine as he was searching for his glasses while holding his head. Once Gowther spread the message through Broadcast, King along with the other Deadly Sins attack Meliodas and Hendrickson with all of their powers, however, Diane was in tears for attacking Meliodas. It was revealed that Meliodas is charging up for Revenge Counter as it is Meliodas ultimate technique in which he finally killed Hendrickson, ending his reign. Diane watches in sadness as Elizabeth was taking care of Meliodas wound, feeling insecure about herself again. Once Bartra returned from Camelot with Merlin by his side, he forgave the Holy Knights and cleared the Deadly Sins name for their crimes. As the others started to grieve over Hawk's death, the black matter on the pig's dead body started to disappear and revealed that Hawk is still alive, but shrunken. However, everyone was still joyful for their friend being alive.

Post-Kingdom Infiltration arc
As Liones was being rebuilt, King ended up being trap under a column due to helping an old man, Diane appeared in regular human size as she lifted the column with ease and surprised everyone. King was shocked to see Diane in regular size and in different clothes, but revealed that Merlin offered her magical pills called Minimum Tablets that allowed her to shrink for seven hours as her clothes are being repaired. King continued to stare at Diane which made her ask King if she looks strange in western clothes or being small in general. King, however, revealed that he doesn't care if Diane is big or small, she is still Diane which made her smile. King asks Diane if she could invite Meliodas to the National Foundation Festival despite calling himself stupid in his head as he wanted to ask Diane, to his shock, Diane asks King out instead. The next day, Diane wore the new outfit Merlin made her which she told the latter she loved it, despite having a hard time to choose between the two she made which confuse the mage as she didn't make two. Diane grew greatly upset when Ban didn't wear his new outfit as Diane and King picked it out for him while being rude about the outfit as he didn't care enough to notice it.

During the National Foundation Festival, Diane in her regular size serves food and ale to the patrons of the Boar Hat in celebration from night to dawn. Later back in her true size, Diane attends the award bestowment ceremony with the rest of her fellow Sins except Ban and King who left for the new Fairy King's Forest and Escanor still missing. When the king decides to go on with the ceremony without the missing three, Diane and her fellow Sins were surprised of Meliodas' sudden objection due to some Holy Knights talking behind his back, revealing to be three members of the Pleiades of the Azure Sky: Deathpierce, Dogedo, and Waillo. Witnessing Dogedo challenging Meliodas, Diane and the others were confident that it's obviously their captain's win as the Dragon's Sin of Wrath defeated the Platinum-ranked Holy Knight easily. The Serpent's Sin of Envy remains clueless to Hawk's sudden breakdown of his inflated ego after the talking pig read her Power Level through Balor's Magical Eye After the issue settled and the ceremony over, Diane accompanies the group heading to the castle in meeting with the king before running into Gilthunder, Howzer, and Griamore. At the throne room, the Serpent's Sin of Envy was slightly disturbed when Bartra informs them of the omen of the Holy War still growing and a growing threat in the south of Britannia, Camelot. Outside of the castle, Diane discusses with the group before experiencing a sudden earthquake unaware of the Demon Clan's revival and notices Meliodas' expression changed into an angered look with sweats dropping in fear.

Albion arc
Having regained her lost memories at some point, Diane switched to human size and searched around the capital looking for King only to bump into Elizabeth in her new clothes. Escorting the princess to the Boar Hat, Diane expresses her frustration of King not being there with her and later on supports Elizabeth's love for Meliodas after revealing that she now remembers her past with King as she cries in tears. Later, Diane came crashing into Merlin house in tears, begging Merlin to find King while Elizabeth try to calm her down and Merlin tease saying he might have turn invisible. Merlin then told Diane that if she stops thinking about him, he might pop up and told her that they should get ready for Camelot soon. As the two girls left the house, Diane spot Meliodas and ask Elizabeth to confess, but the princess left in embarrassment while Diane chase her.

While cheering Elizabeth, the two waitress came across a confused and puzzled Zeal who doesn't even remember who he is. Diane spot Guila and Gowther who quickly rush over them to help Zeal, but Guila doesn't even remember who her little brother is. A confrontation with Gowther soon after reveals that Gowther had manipulated both sibling's memories; Guila's memory manipulation occurring during the battle between Ban and Meliodas. It is during that battle, Gowther had noticed that both Ban and Meliodas (who despite suffering heavy injuries), increased in power level. After coming to the conclusion that feelings of love are what caused this change, Gowther switches from studying friendship, to love, using Guila as his makeshift lover. Gowther attempts to convince Diane that the memory manipulation was necessary, as it is what helped suppress the Demon Blood within Guila at the time. Revealing that he has made Guila's memories a much happier one, Gowther asks Diane and Elizabeth which set of memories Guila would be happier with. Diane disagrees with this, asking Elizabeth to go get Meliodas and Merlin. Gowther attempts to stop Elizabeth, but is stopped by Diane. Here, the battle between the Sin of Lust and Sin of Envy begins.

After using Blackout to put the surrounding unconscious, Gowther attacks Diane with several shots of her Twin Bow Herritt. However, Diane manages to evade them with her dance. Diane tries to counterattack with her golems Fillet and Loin, but Gowther uses Hijack to control the golems. Diane attacks strongly with her golems, crying out to Gowther to open her eyes.

Soon, Diane came out victorious after defeating Gowther while still suffered some injuries while telling Elizabeth to look after Guila and Zeal while Gowther sulk in his defeat. After Meliodas commands Gowther to restore Guila and Zeal memories Guila then apologizes to her unconscious brother for how she treated him. Diane then observed as Merlin used her Absolute Cancel on Gowther she was then surprised to see her teammate was actually a doll. There she understands that Gowther's words about getting a heart were serious.

Diane was later taken to Camelot along with the others to stop an Albion from destroying the kingdom. After Meliodas destroyed the Demon, another Demon appeared who happened to be Galand of the Ten Commandments.

While Galand has a hold of Meliodas in their battle, Diane takes revenge as Merlin brings her back to her original size and transport her clothes and her Gideon. However, Galand kicked it towards her head causing her to go out of commission.

Istar arc
Later she began to gradually lose her memories about the Seven Deadly Sins, because of Gowther's powers, Lost World. As she finally forgot about the whole time spent with her comrades, she leaves Camelot to come back to her hometown, Megadozer.

On her way to the homeland of the Giant Clan she meets again Galand along with Monspeet, another one of the Ten Commandments. As her situation seems desperate, she is unexpectedly saved by Matrona. Diane is disconcertedly happy to see her alive, but Matrona hits her in the stomach leaving her unconscious. The two manage to escape from the two demons.

Great Fight Festival arc
Sometime later, Diane is shown watching Matrona dancing. Upon pointing out that dancing looks more fun than fighting, Diane is surprised to hear Matrona state that her fighting days are over and that she would become a dancer. Diane begins dancing, but Matrona considers it terrible much to the Deadly Sin's disappointment, scolding the kids who playfully make fun of her, but quickly changes her attitude when Matrona talks about Zalpa. She explains that it was her kindness in sparring Zalpa that lead to her own survival and thanks Diane for it.

Matrona mentions the Ten Commandments and instinctively Diane falls to the ground, remembering her experience with them. After some encouragement from Matrona, she aggregates her courage and decides to try dancing once more. Matrona then explains the concept of Drole's Dance and the legend surrounding it which fascinates Diane, despite being confused by the explanation. However, she decides to practice by herself, where she begins questioning her memory loss and the changes that have been made. Her reminiscing is cut short when she experiences a similar fear to that of the ten commandments. She notes the presence is weaker as a Blue Demon passes by her, and proceeds to examine the pamphlets it was carrying.

After Zalpa's children Sol and Della injured and can't be healed again, Matrona decides to head and join the Vaizel Fight Festival to find a way to heal Sol and Della. Diane follows Matrona and brings her Gideon after Zalpa ordered her.

Arriving at Vaizel, Diane and Matrona discovered that the whole city turned into a giant maze. In order to reach the tournament place, both of them must pass into the center. Diane and Matrona try to cheat by destroying the maze wall and jumped through the maze but failed as the wall keep generating, proving that the maze was created by someone. Somehow, Diane got separated from Matrona and encountered Elizabeth and Hawk who also got separated from Meliodas and the others.

Due to her memory loss Diane shows her hostility to Elizabeth due to being a human and refused her help. However, Diane prevent Elizabeth's death from falling into a gap and in return, Elizabeth effortlessly removes giant leeches that attack Diane, making her start to believe Elizabeth's claim that they are actually friends and know each other.

Diane, Elizabeth, and Hawk were ambushed by multiple fake Meliodas who later revealed as Prankster Imps and immediately saved by Gilthunder and Howzer who also participated in the festival with the other from Boar Hat. Diane who still lost her memory doesn't recognize them, even one of her Seven Deadly Sins comrade, King. Later, an Earth Crawler appeared and attack them. Diane requested Hawk to be on Elizabeth's side while she, Gilthunder, and Howzer performing a team attack to defeat the monster.Just when the three cheers, the Earth Crawler begin to counterattack, making Diane, Gilthunder, and Howzer cornered. However, Gilfrost, a participant of the festival come to their aid and easily defeat the crawler.

Diane's group finally reach the end of the maze, where all are received by two of the Ten Commandments as participants of the Fight Festival. There, one of the Commandments is asked to create a proper battlefield, surprising both Diane and Matrona upon hear that his name is Drole.

When the participants are divided in teams of two, Diane is paired with King. This one is happy to see her, but Diane still without any memory of him is confused when he says her name.

Diane and King are placed to fight with the warriors of Drole and Gloxinia, the golem and the flower doll. Diane, believing King to be a human child, puts him inside her breasts to protect him while she confronts their opponents. Diane worries when King begins to bleed even though he hasn't received any damage, but it's revealed that he's just getting a nosebleed from being buried in her breasts.

When Diane is knocked down by the servants, King asks her to let him fight. Diane refuses claiming that a human child should not be at the festival. King tells her that he is a fairy and a member of the Seven Deadly Sins like her, but Diane does not believe her because he has no wings. King tries to prove it by transforming into his fat form, scaring Diane and causing her to throw him out of her chest.

When King defends the servants with Form Five: Increase and Form Two: Guardian, Diane is surprised that he really is a fairy. When he tells her that his real name is Harlequin, she gets confused about what to call him. King tries to confess his feelings, but she interrupts him by telling him that Guardian had been defeated.

Diane blocks a hit from the golem receiving a bruise on her head, allowing the flower doll to restrain her from the neck with pods. When the golem was about to pierce his heart, King released the true form of Chastiefol, stopping the golem with True Guardian. When King tells her that he will not allow her to go through more suffering, Diane wonders what kind of relationship she had with him.

Diane is impressed to see that King manages to defeat the golem in one blow, but is concerned about him to see him exhausted. There, the flower doll catches her all over with her lianas, but King saves her with True Increase. After the doll is defeated by a stroke of True Chastiefol, Diane jumps to save King from the attack of the Drole golem, stating that he can not let go that he has risked his life for her.

Diane asks King to tell him what is between them when they have finished the battle. She tries to face the golem Drole with Fillet and Loin, but they are quickly defeated. King explains to her that golems without a consistent image cannot have real strength, so she must create something in what she believes from the bottom of her heart. Diane then creates golems in the image of her friends, Matrona, Elizabeth, Meliodas, Hawk, and King. The first three get to fight Drole golem, but are easily defeated. The King golem, however, defeats him in one fell swoop. Diane says the golem is like that because she sees King as someone really strong.

When Escanor and then Meliodas attack Drole and Gloxinia, Diane ends up being taken along with everyone else as a hostage by Drole in their hands on the ground. Inside, all are forced to consider retiring. When Matrona insists on staying for Sol and Della, Diane tries to convince her to trust her and that they will be fine if they escape.

Diane is then teleported to Liones along with the others by Gilfrost. There, all observe through a crystal ball the fight of Meliodas against Drole and Gloxinia. When Meliodas' identity begins to be questioned, Diane affirms that he is a good person.

When Meliodas is confronted by the other Ten Commandments, Diane shows Matrona that despite the immeasurable power they possess, they would never have helped Sol and Della.

Along with the rest, Diane can not do anything but mourn as Meliodas is killed by Estarossa.

Memories of the Holy War arc
After Meliodas death at the hands of the Ten Commandments, Diane and King take refuge in the Fairy King Forest along Matrona and her family.

One month later, with her memories still lost, Diane takes a bath in a lake, but horrifies when discovers that King was also there. After hiding her nudity, Diane blames King for not check over the area before. In that, Diane says that if what King says before about it has not sprouted it is probably because he was ashamed and that he is still who he is. When King tries to clarify that he was talking about his wings, they both go back to seeing each other naked.

After getting dressed, King discusses with Diane about Meliodas's death and the rampart of the Demon Clan over Britannia and the eventual fall of Liones into his hands. When Diane asks why the forest was not attacked by the demons, King reveals that the forest is protected by a magical barrier that prevents even the Ten Commandments from detecting it. Diane thanks King for allow her and Matrona to hide there. However, King claims that Drole and Gloxinia could still find it as ancient fairy and giant kings. Diane claims that they must still alert for them, although she recognizes that in their current state, any of them have an opportunity against the former kings.

Upon reunites with Matrona, Diane and everyone in the forest have a good moment to dance and mashes merry, including Gerheade. However, King and Diane suddenly disappears.

Drole and Gloxinia resurface, abducting King and Diane inside their Oredora, unleashing a battle between them. Diane attack Drole repeatedly with Gideon, but the latter stays unimpressed at the giantess's continuous attacks, enduring every strike. Diane is then pushed back by a single blow from Drole's palm, saved only by her Heavy Metal. Impressed by his strength, Diane decides to use her strongest technique and uses Crazy Rush to attack Drole with enormous earth punches. Initially, Diane thinks that Drole evades her attacks because he is afraid of them, however, she then realizes that he is actually dancing and thanks of that, all her magic is dispelled. Drole then fights back and beats her into the Ore Tree's wall, leaving her fatally wounded despite her using Heavy Metal. Drole claims to Diane that a giant's strength does not come only from their muscles, but its connection to the earth. However, instead of killing them, Drole and Gloxinia declares that they will train both of them in order to be surpassed by them.

Gloxinia then uses Form Seven: Moon Rose's Drop of Life to completely heal her wounds. King and Diane are skeptical at first, asking about Drole and Gloxinia's intentions. These two explain to them about certain crossroads in their fight against the demons 3,000 years ago that made them take sides with the Ten Commandments. Gloxinia and Drole declares that want to put both her and King in a trial to verify the rightfully of their decision, adverting that they will grow or die as a result. Diane accede to do it, trying to persuade King of the opposite at the same time as him. At that time, Drole and Gloxinia used a spell that was taught to them by an "old and dear friend", releasing a great wave of light.

Upon awakening, Diane is then sent with King back to the past during the Holy War, and finds herself in the body of Drole 3000 years ago. While they wonder what is happening to them, they both feel the magical power of a member of the Ten Commandments, but are surprised to discover that it is Meliodas, who receives them naturally. Diane and King do not understand how it is possible that he is still alive, which Meliodas takes as a joke. Although they try to explain to you that in reality they are not Gloxinia or Drole, Meliodas does not take them seriously. There, someone else arrives claiming that the reunion is complete, dealing with someone who looks exactly like Elizabeth. However, seeing his huge white wings, Diane and King realizes that it is a Goddess.

When Elizabeth and Meliodas leave the scene, Diane and King go after them. There, King tells Diane that they are in the Britannia of 3,000 years ago, before Drole and Gloxinia became Commandments, but does not understand how it is possible that there is a Goddess equal to Elizabeth, also tells Diane that they must maintain the appearances of Drole and Gloxinia at the moment. When Meliodas reveals that the Valley of the Fossils was being attacked by the Demon Clan, Diane and King are shocked to witness the horrible massacre perpetrated by the hordes of demons. Seeing Meliodas fight, both are impressed with the incredible power of Meliodas. There, a demon with an incredible power approaches them, King tells Diane to run, but Meliodas warns them that it is Calmadios the Piety of the Ten Commandments and that they will activate their Commandment if they flee from him. When Calmadios attacks Diane, an annoying King avoids his attacks and releases a powerful ray from Basquias over Calmadios. Diane reveals to be all well, impressed with the incredibly endurance of Drole's body even without Heavy Metal. In the end, Diane manages to use Giga Pick and Giga Lock to beat Calmadios along with King and Meliodas' Full Counter. Although King says that they should not let down their guard given the large number of demons that remained, he and Diane is surprised to discover that everyone has left. Elizabeth reveals that she convinced everyone to abandon the battle, which surprises Diane and King. There, a human thanks them for saving them and identifies them as members of Stigma, the alliance between the Goddesses, Giants and Fairies.

Diane and King follow Meliodas and Rou to the headquarters of Stigma, the Fairy King Forest. In the way, Diane talks witch King about the previous battle being the trial that they must supper, but King points that it was not since they still in the past. In the Light of Grace, all are received by the Archangel Ludociel. Later, Diane was training along a couple of giants, beating them with easy. King tries to tell her about the great concentration of magic that he was sensing, but Diane not listen to him.

Soon afterwards, the demons start moving towards the headquarters of Stigma following a trap planted by Ludociel. Diane leaves with King to support Meliodas. After watching Elizabeth saving Derieri and Monspeet from their Indura Transformation, Diane stops Ludociel's attempt to kill the two Commandments, claiming that it is a cowardly action. There, Diane notices a loss of magical power from the Forest, and she and King rush there.

In the way, Diane talks with King about their experiences, claiming that she can understand the feeling against who kill a dear friend and matches with King's surprise for the Goddess Clan violence. However, the both are surprised by Gowther, who reveals himself as a member of the Ten Commandments. Diane hurry King to the forest, but is apparted by him to prevent Gowther to use his power on her. King reveals that Gowther was who stole her memories, so Diane demand to him to restore them, but King reminds her that it was happened in the future. Asking about it, both reveal Gowther their true identities, something that Gowther finds fascinating. However, he starts to act strange like if he was talking with two people at same time. There, Gowther reveals all the truth about that he is a puppet created by the real Gowther member 500 years ago when he was imprisoned after being forcefully bestowed with the role as the Selflessness Commandment, using the puppet as a way to maintain contact with the outside world. Diane is shocked by that revelation. There, a portal opens and the true Gowther appears before both of them. Upon knowing that the humans are taking a rebellion against Stigma, King decides to rush to the Forest, while Diane stays behind to talk to Gowther about ending the War.

After King leaves, Gowther asks Diane if he is her lover, which embarrasses her. Gowther affirms that both have a deep and sincere relationship since none was affected by his commandment. Diane asks if he really can finish the Holy War, which Gowther says is possible. Diane explains that the war is over in the future she is coming from, to which Gowther says his death will not be in vain. Diane is scared at his claim, asking what would happen to the doll if he dies. After a few words of farewell with his doll, the real Gowther asks Diane to take care of watching his doll in the future and guide him on the right path. Diane accepts do it with pleasure, and Gowther, in his thanks, restores her lost memories.

However, their conversation was cut short by Zeldris appearing who pretends to return Gowther to his prison. Diane told both Gowther to run while she held him off. Diane pretend to fight, but was defeated by a single kick, even her magic gets sealed, letting Diane impressed with Zeldris's incredible strength. Zeldris then offered her (as Drole), the choice to either die, or join the Ten Commandments, and even referenced a life of isolation and violence Drole despised, something Diane found very familiar. Instead of choosing, though, she ran from it.

This choice to run was deviant enough from the past that she came back to the present, shocking Drole after telling about her choice. There, she says to King that she loves him and kissed him.

Corand arc
After passing their trials, Diane, along with King, finally reunite with the Seven Deadly Sins through Oslo's portal. Diane tells to the other sins how happy she is to see them again, wishing that the captain were still alive. When she realizes that she landed right on top of Meliodas, she is shocked at first to see him but quickly get happy to see that he is alive.

Meliodas tells Diane that there is something different about her, to what she replies she simply got her lost memories back, much to Gowther's surprise which claims that is impossible to restore purged memories. Diane says that he is wrong, that precious memories never disappears. Then she declares that she is going to help him to reclaim his "heart" so she could keep the promise she made 3000 years ago. King Bartra explains the situation and shows Gowther the heart he once had, causing him to remember scenes from his past. Gowther then suddenly runs off. Diane asks Merlin for one of her pill to shrink to human size and goes to chase after Gowther with the other sins.

As Gowther is about to purge all of his memories, Diane stop him with a drop kick. When Diane confronts him about his heart, Gowther tells her to not interfere and tries to hit her with energy arrows, but Diane effortlessly dodges all of them. Gowther is shocked when he realizes that Diane power level rises as she was dodging his attacks, revealing her power level to be 15,100. Diane claims she could easily keep dancing and make it higher, but she doesn't want to fight him, and she just wants to help him. Calculating his chances of winning as low, Gowther tries to escape, but King block his way. He then tries to use Lady Veronica as a hostage but due to her resemblance to Nadia, but he can't do it, so he tries to purge his memories once again but Diane quickly stops him.

Merlin appears and explains the reason behind Gowther's behavior. Diane gives words of encouragement to Gowther. These words reach Gowther, who regain his original magic power thanks to that, and heartfully thanks Diane.

Days later, Diane along with Elizabeth visits Elaine to see if she is doing well. While they are chatting, Diane suddenly remembers that she saw a person who was an Elizabeth look-alike, and tells her.

Later, the Sins have a celebration in the fixed Boar Hat and drink. During the celebration, the Captain drinks a barrel of alcohol, and she tells him to chug. After talking about how their allies have grown and how they're all together again, Diane does a toast with the other Sins. Then she asks Gowther how did the Gowther (the demon) end the holy war, however Gowther couldn't say anything yet and Diane apologizes for putting him in a tough position. As Merlin points out that Zeldris is still out there and that his power is unknown, Diane tells them that the Demon King lent power to Zeldris and is his representative. The discussion ends with Meliodas telling them that freeing people of the commandment and liberating Camelot is top priority right now.

After Elizabeth told Diane and Elaine what Zeldris told her, Diane becomes shocked that she was the Elizabeth from their training. Diane tells her that it was rude of the captain to brush off the conversation with Elizabeth. Diane then tells Elizabeth that she will help her get her memories back and is cheering for her.

A while after their conversation, Diane hold back Elizabeth, who is telling her that she needs to let Meliodas know about Barzad being bitten by a werefox. After Elizabeth faints, Diane thinks that the curse moved to Elizabeth, only to be corrected by Meliodas saying that her memories are returning. Diane happily tells King about how Elizabeth was the reincarnation of the Elizabeth 3,000 years ago. She is then silenced by Merlin but continues to say that Meliodas was being mean for not answering Elizabeth's question. Diane and the others become shocked when Meliodas tells them that Elizabeth will die in three days.

Diane starts crying when Meliodas explained the curses that he and Elizabeth have. She asks him what will happen when the curse is broken. Meliodas responds that his eternal life and her perpetual reincarnation will stop. Meliodas reminds Diane of what they have to do right now.

While the road to Ordan is resumed, Diane stays with Elizabeth feeling guilty for having driven her to recover her memories. Escanor tells him that he was the one who put Elizabeth in that condition without considering it, but Diane insists that it was her fault. Hawk intervenes saying that it is nobody's fault.

When arriving at Corand, Meliodas is deceived by an illusion of Zeldris, causing that it finishes captured by Melascula. Upon entering his search, the Sins are faced by revived skeletons of the victims of the massacre in Corand. At first, Diane manages to deal with the skeletons without problems, but when the skeletons gain more strength from the negative emotions of Meliodas, her attacks become less effective, as one of the skeletons manages to hurt her in one fell swoop. Even so, Diane manages to defeat them quickly with an attack of Rush Rock powered by her new abilities.

When the last soldier explodes when he can not bear all the power of Meliodas, the vengeful souls of Corand begin to expand. Before the others could avoid it, the spirits end up possessing Diane. Diane is consumed by them, asking the other Sins if she can kill them.

King tries to reason with her, but Diane unleashes her Drole's Dance, increasing her power level to 48,000. Everyone questions to fight against it, but King insists that they must stop the spirits that possessed them. Although King tries to make her reason, Diane sends him flying with a kick, saving himself only by Helbram's helmet.

Escanor decides to take action and gives Diane a hard blow to the belly. Diane, however, is replenished enough to hit back.

Gowther decides to intervene to save Diane and uses his Invasion to enter into her mind. There, Gowther finds Diane's conscience being tormented by the guilt of putting Elizabeth's life in danger. Gowther intends to get her out of that, but the vengeful spirits interfere by claiming Diane's body as their own. After being expelled, Gowther was hit hard by Gideon.

Gowther says he will not let them do what they want with Diane's body, but they happen to hurt Diane with Gideon's tip. When the other Sins are unable to stop them, the spirit of Helbram intervenes revealing himself as responsible for the massacre at Corand and says that with whom they should direct their hatred. Diane crushes the helmet and thus destroys the spirit of Helbram, but the spirits continue without appeasing their desire for revenge. However, an aroused Elizabeth appears and frees Diane with Let's There be Light. Diane asks her why she takes a chance on someone like her, while Elizabeth says it's because she's her friend.

After Elizabeth healed her wounds, Diane is shocked to discover the relationship that Elizabeth maintained in the past with Merlin, with her calling her "Big Sis Sis". There they are interrupted by Melascula who decides to face them all assuming her giant serpent form.

After Ban was saved by Elaine and Elizabeth, Diane creates several spines of earth to force Melascula to go towards her and to strike a blow and a hit from Gideon, that leaves her totally wounded, leading Melascula to say that her strength was comparable to that of Drole.

Diane witnessed with concern the fight that broke out between Escanor and a Meliodas consumed by his Assault Mode and lack of emotion. After Escanor manages to contain Meliodas, Diane calls him the strongest of all, leading Escanor to point out that he said something very absurd. After Escanor falls prey to the wounds he received in battle, Diane is alarmed believing that Merlin hurt him in one blow.

Back in the Boar Hat, Merlin declares that Escanor will not be able to recover quickly from his wounds and that Meliodas will be turned into an enemy when consumed by his lack of emotions. After locking Meliodas with Elizabeth in her Perfect Cube, Merlin declares that Diane, King and Gowther will be the only ones who can fight if something happens on the way to Camelot.

Outside, Diane talks to King and Gowther about what will happen to their peers and hopes that Meliodas can return to what it was before.

Prelude to the New Holy War arc
Following the road to Camelot, King turns the destroyed helmet of Helbram into an incline for Diane commemorating Helbram's last wish. Diane is pleased with the gift, promising treasure it. Diane is also placed with the earring that King made to Gowther with the fake heart that he used to shroud, stating that it is a commemoration of Nadja. Although she is disappointed that Gowther calls it a useless thing, Diane is glad that Gowther really appreciates it. At that moment, everyone is alarmed to see that one night suddenly is consuming the sky.

Determining the presence of an enemy in the Boar Hat, Diane rushes to taking Elizabeth and Meliodas out. In that, an old demon appears to analyze the powers of all. King asks Gowther if he knows him, and he and Diane being shocked when he reveals that it is Meliodas' master, Chandler. Chandler proposes that they give Meliodas and Elizabeth and let them go, but they all refuse stating that they will never betray their companions. There, Chandler uses Microscopic in Diane to shrink her. Diane affirms that even in her small size she can fight, but she looks dejected when she sees that she has lost her clothes.

While Chandler unties his Meteor Works, King manages to escape and take Diane with him in the sky. King and Gowther join to create their Combined Technique: Celestial Arrow. However, Gowther warns King that Chandler can use the Full Counter, to which alarm Diane, but states that he must wait for him to give the signal for the attack to strike, King says he relies on him. Combining an illusion as decoy, Gowther manages to evade the Full Counter and make the hit of the Celestial Arrow effective. Diane says that both of them are the best.

When Chandler manages to fool them with an illusion of his own and reflects King's Increase, he and Diane are hit by the attack and shot down. Chandler then tries to kill Elizabeth with her Dragon's Claw, but Diane jumps to protect her with Heavy Metal. Recognizing the Giant Clan technique, Chandler uses his usual countermeasure, Crimson Requiem. However, Diane is saved from the acid wave by Ban, as well as Elizabeth, Meliodas and King.

When the battle between the Sins and Chandler is unleashed, the demon unleashes a shower of Grudge Blades on them, but King intercepts it with True Increase. Meanwhile, Ban and Diane run to face him directly. As Chandler states that they are not needed for Meliodas, Diane states that they are the ones who want Meliodas happy. She gives several blows to the demon while saying that to be happy Meliodas needs Elizabeth the same way she does to King, Ban to Elaine or Gowther to Nadja. Chandler calls her ridiculous and tries to attack her with her magic, but Ban avoids taking him from the back.

When one of Chandler's Grudge Blades hits Elizabeth, Diane reproaches her that doing so will cause Meliodas to die too. Chandler simply obliterated her with another blow, affirming that Meliodas would not die for something like that.

Given the distraction caused by Hawk, Elizabeth has the opportunity to heal Diane, Ban and King of his injuries. King, with the help of Gowther, gets a direct hit from True Chastiefol on Chandler, apparently defeating him.

Diane jumps on King's shoulder congratulating him for what he did and says it's not bad to have that size every once in a while. King tells her that she should wear some clothes, so Diane asks her to make something to wear in that size. King then points that is strange that she does not return to her normal size, then, Diane and the others are horrified to see Gowther give in to the effects of the Absolute Order.

There, Chandler recovers assuming his true form and power. Seeing that they are lost, King decides to sacrifice himself to keep Chandler occupied while the rest escapes. After leaving her with Elizabeth, Diane begs King not to do it, but he insists that after all his failures, allows him as a last act to protect her and all. When Chandler's attack on them is unleashed, Diane and the rest are saved by Drole and Gloxinia, who take them back to Boar Hat saying that they will leave the future of Britannia in their hands.

After Drole and Gloxinia locked Chandler in his Orudora, King decides to help them fight him and Diane decides to do it even though she remains small. While the rest flees in Boar Hat, Gloxinia restricts Diane and King with his Emerald Octo revealing that neither of them has enough magical power to keep fighting. There, Drole tells Diane that he can not let her die because she must lead the Giant Clan. Diane does not think she is capable of such a thing, but Drole insists that someone like her is the one who can make the Giant Clan prosper, because of his leadership, they know only battle and death, and she could change such a thing. After this, Gloxinia sends them flying back to Boar Hat. While they escape, Diane and King feel that Drole and Gloxinia have died.

While the Sins regroup, Diane laments the death of Drole. When Merlin says she was cringed, Diane laments that she was not there to help them in the battle and is also surprised to see that her true form is of a tender girl. Hawk says that in that size he can even beat her, but Diane sends him flying with a single punch.

Merlin returns Diane to her regular size with Absolute Cancel at the same time she does it with herself. Feeling the presence of Chandler approaching, everyone comes out to help Elizabeth and Meliodas. However, he finds Chandler kneeling before an awaken Meliodas. Although Meliodas keeps all his memories with them, he decides to leave with Elizabeth declaring that the Seven Deadly Sins are officially dissolved, leaving everyone stunned to reveal that he plans to become the Demon King to break the curse of Elizabeth.

Diane helps clean up the mess in the Boar Hat depressed for what happened. Although Merlin tells them that Meliodas acts that way because his emotions were stolen by the Demon King, Diane insists that they must do something. There, Merlin discovers that Hawk is a living portal to the Purgatory that the Demon King has been using to spy on Meliodas. Diane then suggests that they could reach the Purgatory through Hawk to retrieve the emotions of Meliodas, but Merlin tells her that this would be an impossible task for them, given that it is impossible for a living being to survive in the Purgatory, not to mention that it does not a way they could face the Demon King. However, Ban decides to go alone, although his chances of success are null. Diane worries about him, but Ban insists and is sent to the Purgatory by Merlin.

King and Diane tell Elaine what happened, leaving her distressed by Ban. Diane intervenes to King to try to comfort her by ensuring that Ban returns safely.

Suddenly, everyone feels a powerful presence approaching, worrying about not being able to fight. However, Merlin comes out saying that she will take care of it, since she has a "card" of her own: Melascula. Outside, the intruder is revealed to be Zeldris, who after seeing Merlin in her true form, reveals that she is the one who received the blessings of the Demon King and the Supreme Deity, leaving everyone in dismay. Although Diane claims that they must fight against Zeldris who is incredibly strong, Merlin orders them to let her handle the situation, flying to heaven to negotiate with Zeldris, leaving behind a magic plant to allow her companions to hear everything they say. With this, Diane and the rest discover the past of Merlin in Belialuin and that Meliodas pretends to become the Demon King absorbing all the Commandments.

When Merlin returns after deceiving Zeldris so that someone else will attack him in the vicinity, he teleports everyone to Camelot, where the hostages were fleeing confused. Diane helps everyone to gather the hostages and then send them to Liones. There, Elizabeth appears to have escaped from Meliodas. However, creatures sent by Chandler attack and injure her. Diane takes Elizabeth and kills the creatures, Elizabeth heals herself and reunites with her companions. There, she says that everyone should prevent Meliodas from becoming the Demon King. Diane says that then she will die, Elizabeth hugs her and tells her that even if she dies, she will see her in another life, and they will be friends again.

After rescuing all the hostages, the Sins and Elizabeth return to Liones where they are well received. There, the Four Archangels appear having possessed human bodies. Ludociel reveals himself to be inside Princess Margaret, alarming Diane as she remembers her experience with the Archangel in the trial. In the end, Elizabeth forms an alliance with Ludociel to stop Meliodas from being the Demon King.

While everyone returns to their homes, Diane stays with King taking care of Elaine.

The next day, the Sins meet while Merlin announces that she has decided to go to Camelot on her own to find Arthur. Diane thinks it's too dangerous. Merlin disappears suddenly and returns to the time with Arthur and Cath. Diane reproaches her for actually going to Camelot alone, although Merlin says the important thing was that she rescued Arthur. There, Arthur falls victim to the magic of Cusack and crosses his heart with his sword, to the horror of all present.

New Holy War arc
After the death of Arthur, Merlin, Escanor and Elizabeth attend the meeting to decide the strategy for the Holy War. Diane wishes them luck as they leave, noticing that Escanor is acting strange.

While everyone is preparing for the Holy War, Diane tells King how good he feels with the new clothes that Merlin made for them all, commenting how comfortable and easy to move they are. Diane still claims that the clothes King made her will always be her treasure. King tries to ask Diane to marry after the war, but Escanor interrupts them by claiming they are romantics before a great battle.

Diane joins the Search-and-Destroy Force with King and Gowther as representatives of the Seven Deadly Sins, marching directly to Camelot to face the Demon Clan army.

When the battle is unleashed and the Holy Knights have problems, Diane impresses everyone by using her Queen Ambrace to wipe out almost the entire army together. An Albion manages to get over and shoot a beam of energy, but Diane is protected with Heavy Metal and hits a hard blow with Gideon. There, King and Diane recognize the Omega Ark of Sariel and Tarmiel that manages to eliminate much of the demon army.

In the end, the group manages to eliminate the near complete demon army. Diane suffers some injuries that are quickly healed by Elizabeth. King and Diane make fun of Howzer's new leadership attitude. Seeing the arrogant attitude of several of the Holy Knights, Diane and King point out that everyone is composed as Ludociel. Both get upset when Deathpierce criticizes Elizabeth's words, just as they are surprised to discover that Elizabeth was reasoning with the demons throughout the battle.

King and Diane are alarmed when suddenly Derieri falls on the battlefield. When Estarossa appears chasing her and releases his Black Hound gobbling up the battlefield in purgatory fire, Diane takes everyone underground to protect them, except Elizabeth and Derieri.

When Sariel and Tarmiel have apparently defeated Estarossa, King and Diane are alarmed to see that Estarossa follows them, as well as their new transformation and level of power.

When Estarossa manages to overcome the Archangels and tries to take Elizabeth away, Diane intervenes by creates her Diamond Shield to protect Elizabeth and Guilla, while King attacks Estarossa. However, King's attack is ineffective, just as Estarossa easily breaks Diane's wall and hurts Guila. After eliminating Sariel and Tarmiel for the second time, King and Diane intend to attack him, but are stopped by Elizabeth. There, the princess decides to give herself to Estarossa to prevent him from continuing to kill everyone, being taken away from the battlefield by the demon.

While everyone regroups, King offers to go rescue Elizabeth. Diane worries about he going alone, but then Tarmiel and Sariel who recover their original bodies decides to join him. Diane is still worried for them, but King says to not to do so. When Derieri tries to joins too, Diane shows happy when King says that he trust her, recalling their experience during the trial.

At some point, upon seeing what happen from the distance, Diane decides to separate of the rest of the knights and is transported by Oslo to the Heaven's Theater where King, Elizabeth, Hawk and Gowther were in a desperate situation in their battle. Diane declares that the situation is much worse than she expected, while blocking the rain of light and darkness with her Heavy Metal. King asks what she's doing there, Diane says they both promised to be together forever. Diane shows up by saying she's ready for battle.

While continuing to block the rays with her Gideon, Diane asks to know what is happening there. Gowther uses his Broadcast to quickly update her, Diane is shocked to discover that Estarossa is actually Mael of the Four Archangels altered to end the Holy War 3,000 years ago and learn of the deaths of Sariel, Tarmiel and Derieri.

Diane feels overwhelmed to perceive the magic power of Mael. When a Mael transformed by the Commandments appears, Diane, along with the rest, is obliterated by the Jiai no Kougyoku. King asks Elizabeth to hurry to heal Diane's wounds, however, Diane says she has no pain and begins to feel sleepy. There, King begins to feel the same way, and falls asleep next to Diane.

Gowther manages to use his Sense Opener to undo the effects of the attack that turned pain into pleasure and sleep. Diane jumps behind Mael next to King, Elizabeth and Gowther, thanking Gowther for get her back to her senses. Elizabeth quickly heals them all, and Gowther gives him and Diane the signal to carry out their combined technique.

While King attacks Mael with Yggdra Cloth and Gowther creates many illusions of him to confuse him, Diane proceeds to use her Drole's Dance to gradually increase King's power. Diane is glad to see how his technique initially works, however, Mael manages to use his Shinjitsu no Kane to dispel the illusions and to remove King. Then, using the Commandment of Reticence, Mael creates his Chinmoku no Oogama, slashing King and Diane with it

Diane regrets her carelessness and tries to use her Heavy Metal to protect herself, however, she is unable to use her technique, being forced to evade sickle attacks. Gowther recognizes the seal formed on Diane's leg as the cursed seal of Reticence that has sealed the magic of Diane and King. Elizabeth proceeds to heal Diane's leg and eliminate the seal, but Mael begins to prepare a Jiai no Kougyoku. Diane is alarmed to see that Gowther intends to self-destruct to stop Mael, but is soon incapacitated by the Junketsu no Kou.

Mael proceeds to use his Jiai no Kougyoku, Diane still not finished her healing, can not but watch as Oslo decides to sacrifice his life receiving the attack by all. Diane catches Olso's body when he falls and sadly leaves him in front of King.

Mael shoots another Jiai no Kougyoku again. However, the cursed seal is removed just in time for Diane to use Gideon's special ability, Lightning Rod, to disperse the explosion on the earth. Hawk asks her why she had never used such a useful technique before, revealing Elizabeth that the redirected power seriously harms the earth and the creatures that inhabit it. Diane says that she would never have wanted to use that technique for that reason, but since they are in an artificial structure created with magic, it should be fine. Even so, Diane points out that the attack destabilized the center of the Heaven's Theater and that with another attack it ends up breaking it apart.

Mael launches another Jiai no Kougyoku and Diane once again uses the Lightning Rod to redirect it. There, the Heaven's Theater is broken into pieces and all fall into the void. Diane is saved by Elizabeth who picks her up with her Goddess wings. Diane asks her to forget about her and save King, who can not fly with his magic sealed. Hawk flies to save him and Diane tells him that she count with him.

Seeing that Elizabeth gradually loses altitude by not being able to support her weight, Diane asks her to leave her and leave, but Elizabeth refuses. Mael then appears behind Elizabeth but is beaten away by a transformed King. Diane is shocked to see him in his new form with his full wings.

Seeing his completely different aura, Diane wonders if he really is the King she knows. When King affirms that he is still he, Diane is surprised to understand that he has read her heart. Mael launches another Jiai no Kougyoku. However, Diane and Elizabeth are protected by King's True Pollen Garden. Diane is alarmed that King can not defend himself against Mael while using Chastiefol to protect them, but for Diane's astonishment, King is able to use the other forms of Chastiefol at the same time.

After Gowther manages to return Mael to normal, Diane, King, Elizabeth and Hawk contemplate the terrible release of demon power from Camelot. While they decide to go there, a strange light comes out of Hawk's eyes, revealing to be Ban, who finally returned from Purgatory.

While waiting for Elizabeth and Gowther to return from talk with Mael, King remarks the urgence of reaching Camelot. Diane ask if Merlin and the others are fine and sharing her worries, King grows a great tree from the ground and uses it to create a new suit for him. Being excited by King new clothes, Diane ask him about Chastiefol. There, Elizabeth and Gowther return alongside Mael, who have decided to join them on the way to Camelot.

On the way, the group feels another great magic power reaching Camelot, revealed to be the four Commandments that Mael have expelled, who are coming to rejoin with the five that Meliodas possess. As Elizabeth is alarmed for Meliodas becoming the Demon King if absorbs all of them, Diane points that it will be fine as Merlin still have Melascula's Commandment, but Mael states that it will not make any difference since the Commandments will naturally attract each other.

When Escanor is defeated by the Original Demon and sent flying, Mael catch and save him. Diane worries for Escanor's injuries lending him to blame himself. When Escanor offers Mael to give back Sunshine to him, Diane gets surprised to discover that Sunshine was originally Mael's Grace.

Upon reaching Camelot, Diane uses several rock spikes to, along Elizabeth and King, helps Ludociel to protect Merlin from Zeldris' dark matter.

When Zeldris starts to attack under desperation to stop Merlin, Diane and the others tries to defend her, until King uses True Pollen Garden to protect everyone. After Zeldris is defeated by Mael and the Chrono Coffin is completed, Diane celebrates with her friends the end of the Holy War. However, when Hawk discover that the cocoon was already empty, Diane along everyone is abrumated by the incredible darkness coming from a Meliodas turned Demon King.

However, Meliodas is revealed to have been turned into his father's vessel, revealing that it was the Demon King's plan from the beggining in creating the Commandments and make Meliodas absorbs them to take his young and stronger body for himself. As the Demon King pretends to kill Elizabeth, Gowther takes her out of his attack for Merlin to use Perfect Cube to protect the three along Hendrickson and Escanor. Merlin warns Diane and King that magical attacks doesn't work on the Demon King, so Diane uses Gideon to attack him along King and Mael, claiming that they will protect Elizabeth at any cost. However, any of them is able to make a threat for the Demon King, who easily incapacitates everyone, including Diane.

When Ban saves Hawk from being killed, Diane shows that she is happy to see him.

As the Demon King releases a toxic and caustic storm over the area, Elizabeth and the Sins are protected by King's True Pollen Garden. Elizabeth ask Diane is everyone is fine, but she says that Ban is still outside. After the storm is stoped by Ban and this one fights the Demon King, Diane shows happy to feel Meliodas fighting the Demon King from the inside.

Seeing Ban fight against the Demon King, Hawk encourages him to win, but Diane reminds him that he is in Meliodas' body. Diane is alarmed when the Demon King manages to get he upper hand. Although he says that his voices could never reach the real Meliodas, Gowther manages to use his Invasion and take Elizabeth and the other Sins into the spiritual world where Meliodas confronts the Demon King. Crying of happiness to meet Meliodas, Diane and the others are protected from the Demon King both by Meliodas in the spirtual world and by Ludociel in the real world.

As Meliodas gains new strenght from his friends and becomes able to overpower the Demon King, he ask them to go back and help Ban.

As they return to the real world, Merlin recognizes that the Demon King is in a desperate death throe, pretending to take Meliodas with him in his demise. Merlin states that they must get rid of the Demon King from Meliodas's body right now.

Ban manages to intercept and stop his death throes, and then send him flying with a kick. King, Elizabeth and Merlin then combine their techniques in their Combined Technique: Triple Prison leaving the Demon King trapped. This however manages to break free in a berserk state with his ultimate technique Meat Darkness. There, Diane surprises him with his Diamond Tower, giving Ban the clean guy to give the Demon King the final blow. With a strong fist that sends the Demon King to break the diamond, this is finally defeated and erased from the body of Meliodas.

Despite their victory, the Sins are saddened that with the destruction of the Demon King, they have missed the opportunity to break Elizabeth's curse. She tells them that this is already done, that what she most wanted was for Meliodas to be the same since she would never see him again if he became the Demon King. Elizabeth says she can always reincarnate if she dies, but Merlin asks if she really is okay with that.

There, Meliodas surprises everyone by claiming that he acquired the power to break the curse while escaping from the Purgatory. Despite the dissonance of this and Ban, Merlin uses her Curse Discovery for the curses of Meliodas and Elizabeth to take physical form. There, Meliodas assumes the appearance he had when he was Demon King and tells Elizabeth that despite having made her wait 3,000 years will fulfill the promise he made her. Meliodas easily destroys the two curses and with that Elizabeth embraces him with joy since his long journey has ended, but then it is rectified that their trip together has only begun.

Demon King arc
With the end of the Holy War, the Sins return to Liones and that night all attend to the celebration on the new Boar Hat. There, Diane is seen serving drinks with King. As Gerheade and Puora are impressed with his new appearance and his fully growing wings, Diane thinks that he is only in charge of refills. Diane gives Guila, Zeal y Jericho some soft drinks.

The day after the end of the Holy War, Diane join Elizabeth and the rest of the Sins in the Boar Hat to their journey to stocking up across Britannia.

As they make up a picnic, Diane remains with Elizabeth, Merlin and Elaine while the men goes for food in the forest. Diane starts to talk about their future children and how cute Elizabeth and Meliodas's will be. Elaine tries to change the topics but Diane suddenly suggest that if Meliodas will becomes Liones's royalty if he married with Elizabeth. Diane ask if Meliodas would feel more comfortable as captain of an innkeeper and that way they could still see him anytime they want. Diane finally breaks down in tears not wanting it to be true that Meliodas is going to leave them, Elaine tries to comfort her. She then is surprised when Elizabeth reveals that she already knows that, but that she is fine with it.

Diane exclaims how could she be fine with the fact that the one she loves will disapear from the world. Elizabeth states that if Meliodas forces himself to stay, it will be trouble and that is nothing to do about it. Diane says that she is hearthless.

While their trip is resumed, Elizabeth worries that everyone is quiet and depressed. Meliodas insinuates her saying that they are just tired because they have not gone out to restock in a long time. Elizabeth sets him aside claiming that the conversations they had took away the urge to speak.

Gowther and Merlin realize that they are not heading to Lions, to which Meliodas reveals that he intends to make a stop earlier. In what remains of Edinburgh castle, Meliodas asks everyone to wait while he goes, but Elizabeth decides to accompany him. The two fly inside the huge crater created 12 years ago, where they find a large sphere of darkness, revealing itself to be where the vampire Gelda was sealed by Meliodas.

Upon returning to Liones, Diane goes with her friends to a meeting organized by King Baltra. There, he asks Meliodas to marry Elizabeth and become the king. Baltra ensures that Elizabeth will have no objection, but she says she can not accept. Everyone is stunned when Elizabeth reveals that she plans to go to Demon Realm with Meliodas.

The Sins meet in the Boar Hat discussing what happened. An alcoholic Diane asks Merlin many times what Demon Realm is like, what she explains to her that is a polluted and corrupted land covered in miasma in which no other race than the Demon Clan can survive, as the bodies of the other races prone to rot and decay there, but Elizabeth should be fine thanks to her powers. Meliodas agrees with Merlin that Elizabeth was always that determined, even when she presented him with the demon-hating Stigma 3,000 years ago. Gowther asks him if he has no regrets in that world. Meliodas says he would have liked to see his son having a scruffle with Ban's, but he also has a mountain of regrets. Since even though the war was stopped for the time being, the hatred between the Demon Clan and the other races has not completely disappeared, not to mention those lost during the war, including Arthur whom Meliodas claims to have been a magnificent king. Meliodas laments for only having worried the last millennia to break the curses and have left his only little brother die twice, stating that he deserves to be in hell for all this.

The Sins deny that by claiming that he is a good person, Diane states that Elizabeth would never have fallen in love with him otherwise. Meliodas thanks them affirming that he is who he is today thanks to the fact that the six of them were always there for him. There, Meliodas declares the Seven Deadly Sins officially disbanded.

The next day, Elizabeth and Meliodas has an emotional farewell at the entrance to the Demon Realm. Diane apologizes to Elizabeth for calling her heartless and asks her not to hate her, Elizabeth hugs her and assures her that they will always be friends and ask her to remain next to King. However, before being able to cross the entrance, a gigantic rock is detached from a nearby boulder and falls over Elizabeth, seemingly crushing her to death. Everyone, especially Meliodas, can not help but look with horror that the curse was not broken after all.

However, Elizabeth is saved in the last minute by Merlin who teleport she to safety just in time. Merlin then uses Curse Discovery to reveal that Elizabeth's curse was restored. Meliodas tries to destroy it once more, but as soon as he does, the curse regenerates again. Meliodas concludes that this is because as the curse was put by the Demon King, it continues to exist because the Demon King is still alive. Merlin and Gowther wonders how it can be given that the Commandments have no vessel, King and Diane wonders who could be able to withstand the Commandments when no even Mael was able to sustain four of them. Elizabeth and Meliodas conclude that Zeldris, the only one besides Meliodas capable of resisting the Commandments, has become the vessel of the Demon King.

Elizabeth and the Sins return to Boar Hat to discuss the situation of the Demon King still alive. When Merlin asks who can be the new vessel of the Demon King, Meliodas claims not to know. There, King and Diane feels that the entrance to the Demon Realm is being opened again to which Merlin recognizes is to invoke an Indura. King ask Hawk and Escanor report the situation to the king and the Great Holy Knight while he and the other Sins faces the Indura and Meliodas protect Elizabeth, a last point that Diane makes clare.

In the center of Britannia, the Sins faces the giant Indura that was summoned. Diane gets frightened by the bug-like appearance of the demon. When the Indura accumulates a bulbing in his tail, King notices several magical auras building up there, but Gowther points that those are life forces. The Idura then release a big object from his tail that explodes and scatter in multitude of small objects, what greatly gross Diane. Merlin then discover than they are in fact the Indura offspring. Knowing that the babies will expand throughout Britannia, King determines that they must stop them.

Since their attacks can not reach them, Diane and Gowther let King and Merlin take care of eliminating the Indura babies but Gowther soon sees that they are too many and that they caused a disaster by dispersing through Britannia. King comes to the conclusion that his only option is to use Sunflower to incinerate all the area, but Diane warns him that it would also kill all the humans and animals around. King insists that it's the only way out, but Ban jumps in saying he'll take care of it.

Gowther ask Merlin if Ban is weilding his Sacred Treasure, which Merlin confirms that is Courechouse. Using it, Ban manages to eliminate thousands of Indura babies with an incredibly extended and powerful Assault Hunt.

The Indura then launches the attack, but the Sins manage to finish it with the combination of their attacks. Diane attacks it first using Ground Gladius.

In the Lake Salisbury, in middle of his fight with Meliodas, the Demon King notices that something is approaching at high speed. This result to be the heads of the Indura that Ban, King, Diane, Gowther and Merlin have launched towards him. Meliodas wonder why are they there, to wich Elizabeth say that they come for him. With the arrival of the five, Diane ask Meliodas and Elizabeth why do they act like such strangers.

Meliodas angrily says that it is not their fight and order them to return, but all the Sins express their desire of help. Diane gets funny that Gowther is still unable to read the vibe when this say that they must fight the Demon King anyways if he lose. Diane says she is angry since they are friends so must rely more on them. Elizabeth ask forgiveness, but ask them to understand Meliodas's feelings, since he don't want them involved in all of that anymore just because he loves them.

As the Demon King is taking back from a combined attack of Merlin and Elizabeth, Merlin tell Gowther to take Meliodas inside the Demon King's soul and detach him from Zeldris while they distract him. Not wanting to allow it, the Demon King launch several dark slashes that Meliodas, Ban and King are forced to intercept. The Demon King then attacks the others. Merlin teleports to avoid him while Ban takes Diane, Gowther and Elizabeth.

King uses True Pollen Garden to protect everyone, but is unable to hold on the Demon king's attacks enough for Gowther use his power. Merlin states that fighting the Demon King and protect Gowther and Meliodas' bodies at same time is too difficult for them to do it.

Suddenly, Escanor, having ragined his magic power, stops a lunge of the Demon King with his arm. As this one recites a poem about how he has decided to offer his life for his companions, Meliodas exclaims that he stops because what will happen if he stays that way.

As he starts to fight the Demon King, Escanor overcomes him with Divine Sword Escanor, saying that killing a god is the only way the fire inside him will go out. Diane questions that claim, but Escanor only tells Meliodas to save his brother while he manages the situation, since he will not be able to continue in that world if he accidentally kills the Demon King.

As Gowther archieves to take Meliodas into the spiritual world, Diane is protected along their bodies and Elizabeth in Merlin's Perfect Cube. When Gelda is beheaded by the Demon King, Diane is frightened and Elizabeth covers her eyes trying not to see it. However, Diane is startled to see that Gelda survived to being decapitated.

When King, Ban and Escanor are wounded by the Demon King, Elizabeth ask Merlin to release her Perfect Cube. Diane remarks the risk of her curse, but Elizabeth insist. Merlin do it and Elizabeth uses Invigorate to heal the three fighters. As the battle goes worse, Diane states that the Demon King is recieving no damage and the lake giving him unlimited magic, Merlin states that if the the battle goes on, the effect of the power of Meliodas and the Demon King might destroy Brtiannia.

A sudden whirpool sucks Elizabeth and apparts Diane and the others from her, as a lightning bolt is about to fall over the princess. Fotunately, Melidoas return from the spirit world in time to Full Countering the lightning to the Demon King.

Diane laments that compared to how brave Elizabeth is, she is pathetic even after asking her to rely more on her. Diane then asks Merlin to restore her to her actual size, and then begins performing Drole's Dance. As The Demon King acknowledges that it is the technique that allows the giants to bring their fighting power to its limits, he attacks her with his darkness, but King intercepts it. As her dance ends, Diane asks Drole to give her the power to protect her loved ones.

Diane then unleashes her Mother Creation technique, causing an earthquake that destroys all the land near the lake and lifting an infinity of debris. Diane throws some of them at the Demon King, but he destroys them making fun of an insignificant giant girl dares to challenge him. However, Diane manages to wrap it with so much debris that the Demon King is lifted from the lake. Diane claims that she used to be a loner who hated fighting, but now she has transformed.

The Demon King tries to regain his posture, but Diane continues to throw debris, calling on his friends Sins, Elizabeth, Hawk and especially King who always protected her, were always with her. The Demon King states that there is no reason for her to defeat him, but Meliodas and Elizabeth claim he is wrong that what moves Diane. She then affirms that she is the new Giant Queen and for the future of her people that Drole entrusted her, she cannot lose. However, she states that there is a greater reason why she cannot lose, that it is her dream of living with King.

King then decides to ask Diane that once they defeat the Demon King, they get married. Diane blushes and screaming that of course she will, she throws all the rubble that manages to take the Demon King of Lake Salitsbury, thus cutting off his source of magic.

The Sins regroup as Melidoas declares that their mission to end the Demon King will begin.

When Escanor becomes The One, Diane tries to make Escanor accept that they help him, but Escanor warns her not to forgive disturbance and declares that "the moment finally come".

By witnessing the fight that breaks out, Diane can't believe that the Demon King can go toe to toe with Escanor as The One. Gowther marks that the Demon King is taking damage from Escanor's blows, but Ban says that the problem is time.

The Demon King proceeds to bury a blow to Escanor in the womb, but surprisingly, Escanor's power does not diminish despite having spent his time as The One. Diane and King wonder how it is possible to continue as The One, to which Meliodas reveals that Escanor is turning his own vital force into magical power, pretending to burn his own life. Knowing that means he will die, Diane says they should stop him.

After Ban, Meliodas and King saved Escanor from the Demon King, Diane listens to the conversation between Meliodas and Escanor.

The Demon King is released creating a great monster of darkness. Escanor jumps to face him claiming he did an oath that day and will keep it, that with the life he once wanted to leave, he goes to stake for him and his friends, the Seven Deadly Sins.

Meliodas also jumps in his Assault Mode saying that if he is going to put his life on the line for them, then the only thing right is for them to do the same for him. The Sins go back agreeing, telling Escanor that he has not been alone for a long time. Combining their techniques, the Sins manage to destroy the monster of darkness.

Escanor then tells everyone that it is too late to back out, so he will give everyone an order: Give him the honor of fighting at his side. Meliodas cries saying they are a team until the bitter end.

The Sins together are able to take the Demon King until his limit. There, with the Demon King practically defeated both in the spirit world and in the real world, the Commandments begin to leave Zeldris's body until they completely detaches from him, allowing Zeldris to recover his physical body. However, the Demon King's conscience refuses to let his vessel go and tries to retrieve it. However, Ban snatch Zeldris away before the Commandments can possess him again.

Enraged, the Demon King rises and saying that they observe him, the Commandments separate and disperse in the surrounding area. Diane and King notices that they are taking over every living being, rock and hill. Thus, the Demon King stands with a new, gigantic and monstrous vessel created from the same land of Britannia. King protects Diane from the expansive force with his Pollen Garden.

The Demon King says he can see the faces of people in Britannia crumpled in fear all thanks to the sinful foolies they have commited. He then shouts to be resigned to their deaths because there is no greater crime than opposing the Demon King. However, the Seven Deadly Sins makes a completely confident face. The Demon King demands to know why they have that expression on their faces, to which Diane says that she is not afraid because all her friends are there.

As the Sins launch to the attack, the Demon King uses Death Zero to immobilize them with gravity pressure. He tells them to be slowly crushed out from existence as insects that have no chance against a mountain, as Merlin starts making some chants.

The Demon King continues to make pressure in his technique, claming that he will end the Holy War having taking the life forms whitin that land as vessel. Diane states that even if she doesn't like fighting, she will do it gladly to save those lands. Merlin there uses Limit Breaker, rising hers and her companions's magic power to the absolute top, breaking the Death Zero in the process but she warns her friends that all mut have to rest for a week after that.

Diane launch his Jet Hammer along the other Sins's strongest techniques that Melin combines in a single powerful attack using Power Conversion: Unify. The Demon King believes that his power The Ruler will protect him, but Merlin reveals that the Killer Switch that Gowther have used was not an attack, but a spell that negates his power. The Demon King tries to destroy the combined attack with Death Zero, but the attack proves to be too powerful as Gowther remarks that he is not able to overcome the resolve within their hearts.

Meliodas creates various clones that repeatedly uses Full Counter in the combined attack sending it back at the Demon King, multiplying its power each time. The Demon King cries that if the attack hits him again Britannia will be damaged. However, with Merlin's approval, Meliodas sends the attack to the Demon King, killing him once and for all.

In the resultant destruction, King uses True Pollen Garden to protect the rest of the Sins. Then, he and the Sins fall out of exhaustion as a result of Merlin's Power Limit Breaker. As Mael and Elizabeth heal them, Diane ask Gowhter is he is fine, and he shows that his doll body not feel pain but it could break if he moves too much.

Diane then calls for Meliodas to show that the Commandments are still there. Merlin explains that despite that they defeat the Demon King, his power could revive after decades or centuries. Diane says that centuries fly by in no time, to which King agree but Ban not. Meliodas then unleash his true magical power to destroy the Commandments, causing a resonating between the two Demon Kings that affect the area.

While everyone watches Zeldris and Gelda flying away, Escanor says it's time to do the same because everyone is waiting for them. Sad, they say they must all return together, showing that everyone has already seen that Escanor is about to die since his body is burned to the point that it disintegrates and can no longer move.

Escanor says he has no regrets in his life and thanks everyone for allowing themselves to meet him and meet. He gives each person a few last words. He wishes Diane and King happiness despite not being able to attend the wedding.

King of Chaos arc
Upon returning to Liones, the Sins join the celebration banquet in the castle. There, everyone present murmurs about the burns on Merlin's face. Elizabeth then approaches her saying that they can go outside to treat her wound if she finds it very loud there. Merlin asks if her scars really look so bad, to which Elizabeth replies that she does not care as long as she is well with them. Diane, King and Gowther say the same thing about it being a respectable and incredible brand in which Escanor will always live.

Diane happily states that despite the sadness about Escanor, all the Sins have achieved their goals, with herself having received King's proposal. She ends up realizing that she never knew what Merlin's goal was since she never talked to them about it. King and Ban stress that she could not have been working 3,000 years for nothing and Diane asks to be told and they will help her for sure.

Merlin then declares that as comrades of fate, everyone deserves to know and see it. Merlin then teleports the Sins and Elizabeth to Lake Salisbury where they find Hawk Mama in front of the orb of water that used to be the lake. Merlin then says it's time to start, when Meliodas asks her what, Merlin surprises everyone by declaring that she refers to Arthur's awakening. Hawk jumps over Meliodas and cries for them not coming back for him, to which Diane apologies saying that they don't even known that he was there.

Upon putting herself over the lake, Merlin removes Arthur's body still pierced by Excalibur from the Boar Hat. She says that all the preparations are ready and asks the "princess" if she is ready, to which a voice from the lake asks if it is finally time to meet their master. As the lake water begins to shine and its light reaches Excalibur, Merlin tells Arthur that she was wrong since the sword was not the one that would kill him but the key to advancing to his new stage. Merlin uses the "key" to unlock the door.

After an explosion of light, Arthur wakes up having revived. Diane gets excited for that, however, he begins to act strangely as if his body aches. Merlin says that humans are the most polarizing of all races because they possess qualities of good and light at the same time as of evil and darkness, their very existence is the essence of contradiction, and this contradiction is a form of chaos. She declares the human chosen by the priestess of Chaos will become the ruler of Chaos.

Meliodas asks Merlin to tell him what she did to Arthur, to which she replies that as she already told him, her goal was to awake Arthur, but as the "King of Chaos".

Merlin tells Arthur not to reject the immeasurable magic that was granted to him, but to embrace it. Arthur tells her that he doesn't understand, that his body hurts and asks for help. As his eyes turn black, Arthur starts screaming desperately in pain, to which Meliodas flies to help him. However, seeing him Arthur remembers that the last time he saw him he had betrayed his companions and allied with the Demon Clan.

A strange magic leaves Arthur wrapping it all up, and the surroundings suddenly transform into a bizarre and meaningless scenario. While the Sins are separated in that deformed reality, Elizabeth, Diane and Hawk remains in a single tower wondering what is happening. Gowther looks at the opposite side of the tower without knowing how he can stand against gravity. Hawk exclaims what kind of hallucination it is, to which Gowther states that it is reality.

Arthur then manages to calm down and reality returns to normal. Meliodas then asks Merlin what she did to Arthur and what he means by "chaos". Merlin explains that chaos is a pure and at the same time impure power of darkness feared even by demons and light worshiped even by goddesses; an immense power that is believed that a single intention brought about the world and all races from nothingness, including the Demon King and the Supreme Deity. Merlin declares that Arthur commands chaos and that he is the king who will lead Britannia into a new world. Arthur is very confused by what Merlin says.

Meliodas asks why she awaken a power that is both a blessing and a curse, and demands to know what her desire is. The voice from the lake asks to be allowed to explain instead of Merlin, about the desire made by a single lonely witch who wandered the land in search of chaos.

The being inside the lake, revealed herself as the Lady of the Lake and the Priestess of Chaos, reveals that Merlin hid the truth about Chaos from everyone, including Meliodas. She then goes on to tell Merlin's past about her difficult life in Belialuin and her encounter with Meliodas. Diane is happy to learn that Meliodas saved Merlin and then is surprised to discover that Merlin fell in love with him.

When the Lady of the Lake explains that Merlin sought all her life to resurrect Chaos and that she used the Seven Deadly Sins to kill the Demon King, Diane reacts very angry, stating that Merlin is their comrade and that she doesn't know what she says. However, the Lady of the Lake reveals that Merlin was the one who asked the giant craftsman Dabuzu to create the Coffin of Eternal Darkness to seal the Demon King and the Supreme Deity, also deliberately delaying the spell of the Chrono Coffin for the Demon King to possess Meliodas, she was the one who reactivated Elizabeth's curse after Melidoas destroyed it and finally made Meliodas launch their combined attack on the lake; All in order to achieve her goal.

Diane and King are shocked in disbelief at all that, and King asks Merlin to say something. Merlin explains that to revive Chaos it was not enough to seal the Demon King and the Supreme Deity, one of the two had to be completely destroyed to disrupt the balance. Ban then inquires that she knew that the Demon King would possess Meliodas and still allowed it. Merlin adds that he needed another condition, an explosive magic to wake Arthur with the key, and for that was sending the attack to the lake, although she defended this with which Britannia had been destroyed had she not done so. She also states that she reactivated the curse since she can't allow Meliodas to abandon the mission of destroy the Demon King. Diane break in tears upon discovering the truth.

When Meliodas reproaches Merlin for using the Seven Deadly Sins to revive a being that may never exist, the Lady of the Lake states that Chaos exists and that they have already been face to face with it for a long time. When Diane and the rest no seems to understand, the Lady of the Lake reveals that they have been traveling on it and that all that time has been waiting for her resurrection; leaving everyone shocked to see that she refers to Hawk Mama. There, Hawk Mama is revealed to be a moss shell whose content, Chaos, is now inside Arthur. Arthur then have another episode altering reality without noticing it.

When Cath shows itself happy to see Arthur, he then devours one of Arthur's arms and when it transforms into a monstrous form, the Lady of the Lake tells them that they must retrieve their arm or they will soon know how powerful even a fragment of Chaos is.

Diane asks why Cath did that if he is supposed to be Arthur's friend. While Elizabeth heals Arthur, the Lady of the Lake reveals the true identity of the monster Cath Palug, who was after the power of Chaos witin Arthur. The monster then asks an affected Arthur if he can eat him now, creating a pocket dimension with the fragment of Chaos he had devoured, sucking Arthur, Elizabeth and the Sins in it.

After Arthur destroys the dimension and Cath Palug with a new Excalibur, he faints from tiredness in Merlin's arms. Elizabeth tells Merlin that they should take him to the kingdom, but Merlin just thanks her for healing him and before Elizabeth can reply, she teleports them all away claiming she can't keep up with them.

As everyone is returned to Liones, Diane ask why Merlin and Arthur were left behind, to which King says that it would be awkard if they had come after what happened.

While everyone laments later, Diane asks if the Seven Deadly Sins are truly over this time, to which Ban says everything must end, leaving Diane even more depressed when he mentions that Escanor is gone. While the others express their concerns, Meliodas says they can't leave Merlin and Arthur alone. Although King believes that they will be fine, Meliodas declares that Chaos has not gone yet and that after witnessing the power that Arthur has, if he is not able to control it and yields to his own darkness, he will end up turning Britannia into a living hell and becoming a new threat.

Diane asks why Merlin hid the truth about Chaos from what Melidoas says they should ask her in person. There, Gowther intervenes contemplating if they really don't know the answer to that question.

As Gowther expresses his opinion about Merlin's deep desire as well as theirs, and the Sins discuss whether being of different races can understood each other, Diane understands why Merlin hid everything and agrees that Escanor would also consider all his beloved comrades. Meliodas says that regardless of anything, they cannot leave Chaos unseen and they must do Merlin takes responsibility for what she did. When Gowther asks him what he plans to do to Merlin, everyone feels great magic in the direction that Arthur and Merlin are.

When Cath, who was fighting Merlin, releases a large bunch of beams from his mouth over her, they are all reflected by Meliodas' Full Counter. Surprised, Merlin is healed by Elizabeth, asking both of them why they are there. Elizabeth tells her that it's not just them, revealing that all the other Sins also went.

Merlin rushes to help Arthur confirming that he is only unconscious. Meliodas then tells Merlin that they will make her take responsibility for resuscitating Chaos, so she must devote the rest of her life to protecting and guiding Arthur. Merlin says he didn't have to go there to tell her that, since that was already her plan. Meliodas adds that they also have responsibility for forgiving her foolishness, so he asks her to allow them to protect her. Merlin thanks you by saying that she is indebted to everyone.

As Cath Palug regenerates, he manages to trap everyone except Arthur and Meliodas inside visions. Diane and the rest wake up when Arthur begins to absorb Cath Palug. After returning to reality, everyone agrees to support Arthur in his creation of an everlasting kingdom.

After defeating Cath Palug, the Sins reunite in the streets of Liones as they decide to part in their own ways. Diane and Elizabeth talk about how wonderful a kingdom of fairies and giants will be. King invites everyone to his wedding with Diane that they promise to perform soon, but Ban mentions that they cannot know when a fairy and a giant believe it is "soon".

After always vowing to be friends and comrades, King and Diane leave just like the other Sins.