Merlin/Plot

Introduction arc
Merlin's wanted poster is displayed on a board in Boar Hat.

Armor Giant arc
Using his ability Invasion, Gowther saw in Meliodas' memory that Merlin was the one that attacked and rendered him unconscious, her reasons unclear. Gowther also mentioned that since that time, he had heard many rumors about her, but that none of them led to her.

Kingdom Infiltration arc
When Merlin and Arthur traveled to Liones, she created an illusionary army to get the Grand Masters' attention, as they felt they would not be granted an audience with the king without a large presence. Merlin, disguised with a cloak, snapped her fingers and the army disappeared, leaving Hendrickson and his envoy astonished and impressed. Hendrickson apologized and stated that the king was sick in bed, but still they insisted on seeing him. As he was escorting them to King Liones, Hendrickson attacked them, stating that it was quite common for envoys to be assassinated, even if it was the king of another country. Hendrickson took Arthur while his two Holy Knights accomplices fought Merlin. Merlin easily won the battle and went to support Arthur, healing him after he got hit by Hendrickson's Hellblaze. Arthur told Merlin to stay back while he fought, which caused Hendrickson to reflect on Arthur's and Merlin's abilities. When Arthur was defeated by Hendrickson, Arthur started to blame himself as he was not strong enough, but Merlin, still disguised, told Arthur that he perform admirably and just surviving a fight against a Great Holy Knight of another kingdom was significant. She said that Arthur's first battle was well done and that he should watch Meliodas's battle, as it would serve him in the future, for he was destined to lead Britannia one day.

Later on, Vivian teleported the Holy Knights and the Deadly Sins to a forest in order to prevent them from rescuing Princess Elizabeth. Fortunately, Merlin sends the group back to Liones and begins toying with Vivian, sending her to different locations, enraging her. Vivian attacks her with a strong wind, and as her cloak is torn apart, her identity is revealed. Everyone was either shocked or happy to see Merlin, however, Meliodas was displeased as he believed Merlin was the one who knocked him out ten years ago, and as such wanted answers from her. Yet, he decided to ask her later as they needed to save Elizabeth and Bartra Liones, which Merlin happily agreed with, as she teleported the group to the Royal Chambers. The group was shocked to be in the location so fast and noticed that the Dawn Roar were there as well. As Meliodas was about to try to destroy the door, Merlin revealed that it would be impossible to break in, as it was protected by "Perfect Cube", a spell from the Demon World, and as such would not be destroyed with either strong or weak attacks. Merlin used "Absolute Cancel" and broke the spell, freeing Elizabeth and Bartra. During Dreyfus interrogation, Merlin revealed that Vivian was obsessed with Gilthunder and was willingly to take him and Margaret hostage.

After the situation, Bartra started to cough blood which alarmed everyone until Merlin came and offered to heal him back in Camelot along with Arthur. As Merlin was about to leave through teleport, Arthur told her to wait as he went to Meliodas and offered him the title and rank of Great Holy Knight in Camelot as he believed that they were fated to meet. Everyone was surprised and shocked at Arthur's offer, but Meliodas accepted Arthur's offer, to Elizabeth dismay, as Meliodas believed that since the kingdom was saved, Elizabeth was freed, and Dawn Roar would take over the Deadly Sins' job, there would be no need of him in Liones anymore. Arthur was ecstatic to hear Meliodas acceptance, but Meliodas told him not yet, as he need to stay in the kingdom to restore it, and he still had the Boar Hat to run. Meliodas then asked Merlin if she would rejoin the Deadly Sins, to which she replied not right away and teleported along with the sick Bartra and the depressed Arthur, much to the team's displeasure. As a result, none of the three knew the next serious situation caused by Hendrickson. Later after Hendrickson's death and defeat, Merlin returned to Liones with King Bartra, who had recently recovered thanks to her new hidden technique from the Demon Realm, but Meliodas criticized her for using the king as her magical guinea pig, which the Boar's Sin of Gluttony brushed off so long as the result were good, much to the king's chagrin.

Merlin then listened to the Holy Knights kneeling down before their king, asking for heavy punishment for their sins for blindly following Hendrickson and his evil plot but Bartra instead told them to devote their power to the restoration of their kingdom and thanking the Seven Deadly Sins for saving the country. When Merlin quickly stopped Ban from trading blows with Gowther over Hawk's death, she asked the Goat's Sin of Lust where his armor had gone, and told him that she would get him a new one after hearing his answer. Merlin witnessed Hawk's revival as the Sins rejoiced of their animal companion's return.

Signs of Holy War
The day in which Ban and Meliodas pretend to have their fight, Merlin along with the rest of Liones attend as spectators. There, she reminds both of them that the laws of the Seven Deadly Sins allow them to settle their differences with a fight, but that the others must interfere if it becomes a fight to the death. In order to avoid any damage to the spectators, Merlin encloses Ban and Meliodas in her Perfect Cube to fight comfortably. When Ban is about to use his Hunter Fest, Merlin teleports away to avoid being affected.

During the following days, Merlin detects the presence of Vivian following Gilthunder in secret. When Meliodas asks her to become a waitress at Boar Hat, Merlin accepts only under the condition that Meliodas captures Vivian. After captured, Vivian is held in Merlin's laboratory, using special chains to nullify her magic. There, Merlin asks Gilthunder to decide Vivian's fate after what she did to him and Margaret, but Gilthunder decides not to punish her. Even so, Merlin uses her Curse Engage to curse Vivian and thus causing extreme pain and finally death if she does any wrong against Gilthunder. When Merlin reprimanded her for helping Hendrickson to release the Demon Clan, Vivian claims that they could have controlled them with weapons like the Goddess Amber. There, Merlin states that Goddess Amber can only enclose low-level demons like the Red Demon or Gray Demon, revealing the existence of much more powerful demons within the clan, which causes Vivian to burst into tears.

That night, Merlin fulfills her promise and works as a waitress at the Boar Hat, receiving praise from all the men when they see her in the uniform of the tavern. However, when Meliodas reveals that he planned a routine of singing and dancing for the waitresses, Merlin resigns immediately.

Post-Kingdom Infiltration arc
As Liones was being rebuilt, Meliodas and Hawk were watching over the injured Elizabeth as she slept in her bed. Merlin teleported out of nowhere, and stated that Elizabeth had unlocked her powers without even thinking about it, which had only healed everyone else because she was thinking about all but herself. Even if Elizabeth had some power left, she still would not be heal herself first, which led to Hawk tearing up, believing that Elizabeth should at least think about her health first. Meliodas and Merlin discussed the location of the Eternal Coffin of Darkness, as it was no longer in Liones. Even with Merlin's "Location" magic, she had been unable to find it. However, it was revealed that a strange bird had appeared and flown to the east. Merlin revealed that she had told Arthur that she would be away for a while, as she would rejoin the Deadly Sins for the time being, which made Meliodas glad as it could save them, but still on adge due to her suspicious smile. Meliodas revealed that he still wanted to know what happened ten years ago while Merlin seemed interested in Hawk, calling him a hero which made the tiny pig happy and befriend Merlin. Meliodas realized that he had forgotten something and went back to Elizabeth room while Hawk yelled at him that he should not do anything weird to Elizabeth while she slept.

When Merlin and Margaret appeared in front of Elizabeth's room, Meliodas steps out of the room with a grin which made some of them worried that he had done something weird, until it was revealed that Elizabeth was up and healed for unknown reason. Hawk was overjoyed to see Elizabeth standing again, but wondered why she was moving again. Merlin seemed to know what Meliodas did as it was revealed that Meliodas held her hand and told her that he could not live without her, which made her wake up. At some point earlier, Merlin had given Diane Minimum Tablets to shrink down to human size while the latter's tattered clothes were being repaired for a while. In preparations for the National Foundation Festival, Merlin gave Diane a new outfit and a gauntlet replacing her previously lost one, back at the Forest of White Dreams. During the festival, Merlin, among the crowd of people and Holy Knights witnessed a marvelous display of fireworks. At some point after the festival, Merlin salvaged whatever remains of her Magical Items within her destroyed castle were left, and set up a temporary small castle until her old one was rebuilt. She gave Hawk Balor's Magical Eye as his new ear trinket and explained the fundamentals behind it, demonstrating the analyzing of the passing Holy Knights' Power Levels.

The Boar's Sin of Gluttony unwittingly lied to Hawk that his Power Level was 3000 as a playful joke that fed the talking pig's ego. Later at the award ceremony, Merlin was present with the rest of her fellow Sins and Hawk (who had somehow grown back to normal size), except Ban and King, who were at the new Fairy King's Forest, and Escanor who was still missing. When the king decided to go on with the award bestowing, Merlin witnessed Meliodas calling for the objection and the appearance of three of the Pleiades of the Azure Sky, Deathpierce, Dogedo, and Waillo when the Dragon's Sin of Wrath demanded they stoop forth to have a voice in the matter. The Boar's Sin of Gluttony witnessed a battle between Meliodas and Dogedo which ended in the former's victory and the latter's defeat and unconsciousness, with the satisfied Six Stars leaving the scene. When Hawk begins to panic about his companions' Power Levels, Merlin tells the talking pig that every member of the Seven Deadly Sins' Power Levels are higher than any Holy Knights' and her Power Level was revealed to be at 4710 much to Hawk's dismay.

Much later, the Deadly Sins encountered Gilthunder, Howzer, and Griamore who thanked Meliodas for defending them and Dreyfus, but felt troubled about themselves. Merlin advised them to go out and find the truth for themselves. Merlin accompanied her fellow Sins to meet with King Bartra, who informed them of the growing omen of the Holy War set in Camelot, south of Britannia. Later, Gowther went to Merlin's new headquarter where she gave him strange pills as medicine, which Hawk found tasty. As Diane came in, begging Merlin to find King, which Merlin teases her about, saying he might have turned invisible. Merlin then told Diane that if she stopped thinking about him, he might pop up and told her that they should get ready to leave for Camelot soon. When everyone left Merlin's home, Meliodas walked in, demanding to know what had happened ten years ago and wanting something that was stolen from him. Merlin revealed that she knew that the Demon Clan had been set free and believed Hendrickson was still alive. Meliodas was not worried about him as what he was most worried about is the ones who were set free, as he believed they were the Ten Commandments, hand-picked by the Demon King himself. Hearing, this, Merlin got a bit too excited as the items in her room flew around and asked to talk about this real issue.

Albion arc
Suddenly, Merlin and Meliodas were struck by Gowther's Blackout technique that knocked out everyone in the capital unconscious except for Diane and were believed to be affected as well. But later on, they're revealed to be alright as they searched around the city to find the cause behind the anomaly. There they find Elizabeth regaining consciousness and then the aftermath of the skirmish between Diane and Gowther appearing to be ended in a draw. After the short scuffle has been settled for now with Gowther returning Guila's old memories as well as Zeal's including their breakup of their relationship, Merlin and her fellow Sins confronts Slader who arrived at the scene. The Boar's Sin of Gluttony was pleased to see the Dawn Roar captain and had a favor for him, only for Meliodas to remind her that Slader only listens to the king. Merlin there uses Absolute Cancel to revert Gowther back to his original form as a doll. There she reveals that Gowther is in fact a doll created by a great wizard and ask Slader to take care of him until Gowther´s magic activates again. Merlin and the others returned to the bar where Slader agree to join with them for a while and Elizabeth wanted to join, but Meliodas shut her down coldly to avoid her getting hurt by the Commandment to the displease of others. However, Merlin got a call from Arthur who was under attack from an Albion and teleported to Camelot to battle the giant.

Merlin used her magic to make Hawk Mama fly over Camelot along everyone over her. Upon arriving, they discover the Albion trying to destroy Camelot, but a special magic barrier that Merlin has put around Camelot to protect it from harms stops it, but only for a short while. While Meliodas, Arthur and his men fought against Albion, Liz's Sword was soon broken which Merlin believed it was time for her to return his Sacred Treasure, Lostvayne, that she have found in a bazaar. There, Meliodas used his Sacred Treasure to slay the golem and saved Camelot.

While the group chatted fondly, Galand of the Ten Commandments appeared and challenged everyone to a fight. Meliodas was shocked to see him and Galand revealed that he knew Meliodas and was surprised he had not aged at all for the last three thousand years, but still attacked him. Merlin takes care of Elizabeth, Hawk and Arthur, protecting them with her Perfect Cube. While the Deadly Sins fought bravely, they still lost to Galand, Merlin tries to support them equipping Diane and attempts to teleport Galand away, but the speed of the demon proved to be superior to her magic's. At which point Merlin tried to trick Galand by lying to him until find a way to prevent Camelot to receive more damage. As it turned out, Galand's Commandment of Truth, which turned anybody to stone should they lie to him, turns Merlin in a statue to horror of Arthur. The Deadly Sins were believed to have been killed by Galand, when in reality, his memories were altered by Gowther's Invasion.

Istar arc
While Camelot mages tried returning Merlin's body back to normal, they were not able to, but luckily, Merlin had stored her consciousness in her Sacred Treasure, and revealed that her body could only be returned to normal by the power of a Goddess. The group was still down about losing to Galand. However, Meliodas soon lifted everyone's spirits up by deciding to train more to get stronger, and to figure out a strategy. Even Arthur and Elizabeth would have to awake their hidden powers as well. Meliodas believed the situation was so bad, they would have to bring in Escanor and later went to check up on Diane's health until King popped up to check up on her. When the three checked on Diane, she was shown to have lost all of her memories, up to the point of meeting Meliodas for the first time. While Meliodas and the others talked about Diane's lost memories, King kept Diane company until she started to lose more memories and ran off. Gowther soon revealed that he had uses Lost World on her to test if her feelings for King were stronger than she said. After King punched Gowther, the others followed Diane, who was heading to Megadozer, until they were stopped by Monspeet's fire ball, which Hawk Mama ate, to the others shock. When they could not sense Diane's power level anymore, Meliodas believed she was fine and that they should focus on their training until they met Diane again. Meliodas decided the first thing to do was to head to Istar, the home of the Druids, and the location of Meliodas' stolen strength. On the way, Merlin reveals to his companions the truth about why he took Meliodas's power ten years ago, because it was too dangerous for him to control him by losing himself in his anger, but to fight with the Ten Commandments, they need that power.

Upon reaching Istar, Merlin explains to Slader that they can only enter the sacred land of the Druids if they will break through. After being greeted by Jenna and Zaneri, Merlin is pleased that these two will offer their help.

When everyone decides to enter the Training Caves to strengthen, Merlin says he can not accompany them since she still lacks a physical body. When observing the fight that unties between Meliodas and King, Merlin reveals the nature of the power Disaster of King, able to manipulate the life and the death.

After finally getting his strength back, Meliodas asks Merlin to teleport him to where the Ten Commandments are. Merlin tells him that he knows exactly where to send him by following Galand's presence, but that it will take at least ten seconds for him to bring him back, so he must face what the Commandments do to him at that time. After Meliodas returned safely and defeated Galand, Merlin is surprised by the cat that appears in Arthur's head. After leaving Istar, Hawk reads the new power level of Meliodas as 3,250 which is less than before. However, Merlin tells him that he forgot a zero at the end, leaving everyone shocked by revealing his power level at 32,500.

Defensive Battle for Liones arc
After Grayroad and Fraudrin of the Ten Commandments were able to successfully infiltrate Liones Castle, Merlin, freed from the petrification, appears to stop the former, claiming that she will turn them into her guinea pigs. After freezing Grayroad's eggs to delay the hatching of more Demons and save Howzer from her Five Lost, she engages in a fight with the queen of the Gray Demon. After defending herself from the demon's attacks and kill one of her faces with Exterminate Ray, Merlin is show not affected by Grayroad's Pacifism commandment. There Merlin reveals both her magic ability, Infinity, that lead everyone to call it unfair, and her true identity as the daughter of Belialuin. Utterly shocked, the Commandments are paralyzed of fear and Merlin starts her offensive, ending the fight in one attack by sucking Grayroad in a small test tube with Endless Whirl. She then expresses joy about being able to experiment with such an unusual Demon.

After Hendrickson and Zaratras managed to purge Fraudrin out of Dreyfus' body, Merlin stays with the other survivors of the Commandment's assault on the capital and watches as at first the no longer controlled Dreyfus and Zaratras and eventually Meliodas, who returned from Purgatory, fight Fraudrin. To ensure the group's safety, she arrays the royal family and the Holy Knights in her Perfect Cube.

After Fraudrin was murdered by Meliodas, Merlin met with Escanor who asked how Meliodas was still alive, prompting Merlin to reveal the curse that the Demon King put on him, reviving him every time he died in exchange for his emotions are consumed more and more. In the end, Merlin states that no matter what atrocities he committed, Fraudrin did not deserve to die the way he did.

Memories of the Holy War arc
The night after the defeat of the Commandments, Merlin took care of rebuilding all the damage in the kingdom and castle. The next day, she explains everything to Escanor while he gives her a bath. However, she also claims that the battle is not over as all who were under the control of Zeldris' Commandment fled to Camelot, which is the current headquarters of the Demon Clan. In order to face the next battle, Merlin states that the seven members of the Seven Deadly Sins must reunite to whom Meliodas is agree, so Merlin arranges things to free Gowther from his imprisonment.

Corand arc
While Merlin waits on the roof of the castle of Lions with the other Sins for a prophecy of Bartra about a "full moon" this turns out to be the arrival of Diane and King. After receiving them and hearing about their journey 3,000 years in the past, Merlin says that it could be the temporary regression technique belonging to the Goddess Clan. When Bartra appears and shows Gowther the magical heart that used to belong to him, this one of immediate leaves fleeing. Upon hearing about the "magic heart" that is imbued in the object, Merlin asks the king to allow him to examine it. There, following the rules of the Seven Deadly Sins of always helping each other in times of need, Merlin along with others in search of Gowther.

When Gowther is reached by Diane and King, they try to help him so that he does not erase his memories. There Merlin arrives and reveals Gowther's past with the princess Nadja Liones and how she died and Gowther tried to revive her with his magic heart, erasing his own memories and feelings when he could not do it. However, Merlin reveals that this "magic heart" is actually a common object and that this never had any "magic of heart" since the true heart of Gowther is within him at those moments. Thus, Gowther awakens his dormant feelings and memories, along with his true magical power. Merlin says that Gowther is the masterpiece of the life of a great wizard, so it is not surprising that he has always had a true heart.

Later, Merlin sends Orlondi to Camelot in search of Arthur. While Merlin watches through him from Liones, Orlondi is discovered by Zeldris, who releases his Hellblaze against him, however, Merlin is the one who receives the attack, being seriously wounded.

Merlin then joins his companions in their banquet, asking forgive for her delay. Upon hearing from Diane that the original Gowther finished the Holy War, Merlin and Meliodas are surprised, wondering if it was he who created the Coffer of Eternal Darkness to what Meliodas tells her was created by a giant craftsman. After clarifying the situation of Camelot and the danger that Zeldris represents, Merlin goes saying that they needed a good plan and their absolute cooperation. In the way to her room, Merlin ending collapsing, but Meliodas goes to help her. Meliodas ask her if Zeldris was the responsible for her condition and that she take that risk all for Arthur, a weakened Merlin says that she can not afford to lose Arthur and claims that the young king is her hope.

The next morning, Merlin condition get worse, being completely unconscious and fever in bed. Upon find her, Escanor ask Hendrickson to help her, but his druid powers are unable to do something, as Merlin was under a curse put on her by Zeldris. There, Escanor ask Elizabeth to use her healing powers on her, as Hendrickson affirms that the princess's magic is stronger than of any Druid. After a confrontation with Zeldris, Elizabeth manages to release Merlin from the curse, as she gives her thanks to Elizabeth and Escanor.

After returning to their old armors, Merlin pass to tell her companions about the dimensional distortion that prevents to enter in Camelot by any mean, physical or magical, and that even Absolute Cancel is unable to undo it. Having locating the origin of the distortion in the city of Corand, Merlin states that their next mission is to go there to eliminate the distortion.

Later, Merlin drinks with Escanor hoping to Arthur to be fine. Elizabeth starts acting strange suddenly, saying things related to her past lives. Seeking to confirm what happens, Merlin asks Elizabeth if she recognizes her, being shocked when she tells her that it has been a while since she saw her and asks if she is still living on her own in Belialuin, as well as the Goddess Clan symbols appear in her eyes. When Elizabeth falls unconscious, everyone gathers in her room worried. Merlin claims that her condition may be due to the magic that Zeldris used in her when she released her from his curse. Meliodas reveals that Elizabeth is recovering the memories of her past lives, to which Diane happily says that she will remember everything that she lived, causing Merlin to scold her with taking care of her words. When Meliodas reveals the curse that is on him and Elizabeth, and that Elizabeth will die in three days after recovering her memories, Merlin is the only one of the Sins not to be impacted, being already aware of that fact.

During the trip to Corand, the group stops in Ordan to free it from demons that had oppressed them. Merlin asks Meliodas if it is right to distract from their objective, to which Meliodas tells her that it is their duty as knights to help those who need it.

When they finally reach Corand, they are surprised at the entrance by Zeldris. Merlin tries to warn Meliodas that his presence can not be anything other than a trap, but Meliodas still tries to attack him, turning out to be nothing more than an illusion concocted by Melascula to capture Meliodas in her Cocoon of Darkness.

Upon entering Corand to find Meliodas, the many skeletons that populated the city after the massacre that destroyed it begins to come to life. Merlin identifies it as Melascula's technique that revives the dead through his anger and resentment. Being initially very weak, the Sins have no problems in facing them; Merlin gets rid of several of them with her fire magic. However, Melascula manages to take advantage of the negative energy of Meliodas to give power to her skeleton warriors. Merlin is surprised to see how the strength, speed and resistance to the magic of these is greatly increased. When Gowther is unable to control the skeletons with his Jack, Merlin saves him by destroying them with her Exterminate Ray. Merlin deduces that the skeletons are not moved by nerves that Gowther can control, but by their own resentment and by the enormous dark energy that comes from the center of the city, inferring that this is where Meliodas should be.

Upon Melascula tries to concentrate all the energy in the last skeleton remaining, Merlin anticipates that is impossible for it to sustain the immense power of Meliodas, resulting in its destruction. However, Merlin adverts everyone that the remaining spirits of the dead are trying to take control of them. When Diane ends being possessed by all the spirits and turned against them, Merlin declares that they have no other option that attack her with intention to kill, but King intervenes to prevent it.

Finally, Diane is purified by an awakened Elizabeth, who eliminates all the spirits with her Lest's There be Light. Having recovered all her memories, Elizabeth talks with Merlin about their past together when she was 12 years old, claiming that she become a beautiful woman, which makes Merlin somewhat taciturn. When Elizabeth asks if she no longer calls her "Big Sis Sis" as she used to do, Merlin is very embarrassed. When Escanor asks to know more about it, Merlin recriminates him not to get involved in that.

There, Melascula appears suddenly and assumes the form of a gigantic serpent. When this one is sent to attack Ban after this insulted it, Merlin is protected within her Perfect Cube, taking Elizabeth and Gowther with her.

Suddenly, a giant explosion of dark power destroy the center of Corand. Merlin affirms that it must be Meliodas, who was given freedom to all his demonic power. When Escanor goes with the intention of fight him, Merlin adverts him that in his current state, Meliodas is too much for even him to handle, but Escanor tells her to not worry. Knowing that Meliodas was deprived of all his emotions and feelings to recover his original power and sets free, Merlin traps him and Escanor inside a Perfect Cube, calling Meliodas a fool.

When Melascula is overpowered by Diane and King, Merlin states that the battle was decided at the moment that she underestimates them and chose to fight in that form instead of using her true magic power, affirming that she was too confident. When Melascula is finally immobilized by Elaine and Gowther, the fairy claims to Merlin to kill Melascula, even if that means her own death too. However, Elizabeth uses her Tranquilize to deprive Melascula of all the demonic miasma that gives her demonic powers, returning her to her original form as a harmless little snake. There, Merlin captures Melascula in a test tube as other of her guinea pigs. When Elizabeth calls Merlin little sister, Merlin is embarrassed again.

While the fight between Escanor and Meliodas continues with the demon's advantage, Elizabeth asks Merlin to undo her Perfect Cube so that she stops them, but Merlin refuses because since he can not control his dark power, Meliodas will kill them all if come to be liberated. When Hawk asks what else they can do, Merlin simply states that it's almost midday. Escanor then receives a huge increase of power from his Sunshine, but this still is not enough to stop Meliodas who incapacitates him with a single blow. Merlin affirms that this is the Meliodas recognized by the legends of the Demon Clan and leader of the Ten Commandments. Although Escanor seems to have been defeated, Merlin says that everything comes down to the minute that Escanor assumes his most powerful form during midday, describing him as the supreme incarnation of power, "The One". With that power, Escanor finally manages to defeat Meliodas.

Having finished the battle, Merlin charges Meliodas with her telekinesis while revealing that with the defeat of Melascula, the dimensional distortion on Camelot has been dissipated, but that Meliodas can not go in such a bad condition. Elizabeth asks him to let him cure him, but Merlin reminds him that if he did Meliodas would attack them and nobody could stop him. When Escanor affirms that he will stop him as many times as necessary, Merlin gives him a simple blow, and he falls unconscious.

In the Boar Hat, Merlin explains that Escanor exhausted all his power in his battle with Meliodas, so he is probably in a worse condition than him. By the other hand, Meliodas have lost all his emotions and returned to be the old Meliodas from the Demon Clan. At that moment, Meliodas awakes, but Merlin knocks him again with her Shock Stinger. Merlin tries to lock him in her Perfect Cube, but Elizabeth tries to convince her not to do it. Merlin insists, so Elizabeth asks to be locked with him, to which Merlin agrees only under the condition that she stays to monitor both. Given her appointment, Merlin affirms that Diane, King and Gowther are the ones who will have to fight in case something happens, while in the two remaining days that Elizabeth has left, they think of a way to heal Escanor and recover Meliodas in order to free Camelot.

Prelude to the New Holy War arc
While watching over Meliodas and Elizabeth, Merlin feels the presence of a great dark power that was blinding the entire region. At that moment, an old man appears crying to see Meliodas and when to kill Elizabeth. When this individual manages to undo the Perfect Cube just by touching it with his cane, Merlin realizes that this use Absolute Cancel, affirming that he is not an ordinary enemy. After ordering Elizabeth to retreat, Merlin uses Magic Seal in an attempt to seal the old man's magic, but he responds with Full Counter, revealing being the one who taught Meliodas how to use that power. As a result of receiving her own Magic Seal, Merlin's magic ends up being deactivated, causing it to assume the form of a small child. Seeing her in that form, the elder identifies her as Belialuin's survivor.

When Chandler engages in a battle against the other Sins and Elizabeth, Merlin tries to awaken Escanor to help them. However, because of the artificial night that Chandler had created, Escanor returns to his weak form.

When the Boar Hat is taken out of the battle by Drole and Gloxinia, Merlin who was in search of her Incantation Orb to use Absolute Cancel, hits her head in the middle of the shock and ends up unconscious. After awakening with all her companions around, they explain what happened. Merlin claims that Chandler was a much worse monster than he had imagined. After regretting Gowther's pseudo-death state for opposing the Absolute Order and the microscopic size of Diane, the latter is surprised that her true appearance is that of a girl so tender. Merlin affirms that she must return to her old form as soon as possible, although Escanor prefers that she stay like this a little more. When everyone begins to feel sick, Merlin realizes that it is due to the demonic miasma that Meliodas is expelling, so Elizabeth takes him outside. Merlin asks Escanor if he is well, and he says he is still in a position to fight. After asking for Ban, King tells her that he is with Elaine.

After finding her Incantation Orb and return to her adult form, Merlin helps to clean the room. At that moment, Merlin exclaims in alarm that Chandler is approaching. Upon leaving and discover that Meliodas regained consciousness, Merlin says that it could not happen at a worse time. When he takes Elizabeth and intends to leave with Chandler, Merlin demands to know what he intends to do with her, to which Meliodas reveals that he will become the Demon King to break her curse and at the same time declares the dissolution of the Seven Deadly Sins. When Hawk tries to reason with him and Meliodas speaks to him as if he were the Demon King, Merlin is surprised.

While everyone laments having lost Meliodas, Merlin reminds them that he no longer thinks clearly because the Demon King stole his emotions. When Hawk mentions what Meliodas told him earlier, Merlin asks him to expel him, uncovering to her surprise that Hawk is a living portal between this world and the Purgatory, further revealing that the Demon King has been spying on them through Hawk's eyes. Although everyone is shocked by that, Diane suggests that they could go to Purgatory through Hawk to recover Meliodas's stolen emotions. However, Merlin affirms that it is impossible since they must face the Demon King to do it, and that is also impossible for them to survive in the Purgatory, telling everyone how in the past her father spent a single minute in that place and returned as an invalid elder. There, Ban declares that he is the one who will do it since his immortality would allow him to survive. Merlin reminds him that although his body is immortal, he still has a human soul and that the result is more likely to die in the attempt to recover his emotions. When Ban insists ongoing anyway, Merlin calls him crazy but still recites the spell that sends Ban to the Purgatory through Hawk, reminding him that once there, they can not help him.

While everyone regroups, Merlin examines Grayroad's test tube, discovering that Meliodas took the Commandment of this one without her noticing. Suddenly, Merlin feels powerful presences approaching. While everyone is alarmed because they are not in a position to fight, Merlin claims that she will negotiate with the enemy already having an idea of her identity and that their goal is Melascula's Commandment that she possesses.

Once outside, Merlin discovers that the intruder is Zeldris, stating that it will be much easier than if it were Estarossa. Zeldris says that he has never seen her before, there Merlin resumes her original childhood form asking if he remembers her that way. Zeldris immediately recognizes her as the girl who received the blessings of the Demon King and the Supreme Deity. Upon hearing this, the other Sins are surprised. When the others try to confront Zeldris, Merlin tells them not to interfere and goes to talk to Zeldris in heaven. Before leaving, Merlin releases one of her hairs to create a talkative plant on Hawk for her companions to hear their conversation.

After Zeldris narrates Merlin's past, he asks for her intentions, leading Merlin to ask him why he is helping his brother gather the Commandments and use them to become the Demon King. Zeldris answers only saying that if she gives Melascula, he will forgive her companions. Merlin initially seems to give in, but soon she encloses Melascula in her Perfect Cube, telling Zeldris not to give it to her if he does not give her something in return. Zeldris agrees and Merlin asks him to return them to Elizabeth, but Zeldris says that Meliodas will not allow it. Merlin asks instead to give Arthur, but Zeldris can not give it to her either because he does not know his current situation or if he is still alive. In the end Merlin asks him to release all the knights and civilians of Lioness and Camelot who are under his Piety and to allow them to leave. When Zeldris meets her demands, he demands to disperse the Perfect Cube. Merlin begins to ramble saying that her shoulders hurt and Zeldris warns him that if she tries something he will kill her. Merlin claims that she will not do anything, and at that moment Zeldris is attacked by Ludociel, who was in a Druid Altar near there.

Merlin quickly returns to Boar Hat, revealing to everyone that distracting Zeldris for the Four Archangels to attack him was her plan from the start. Merlin rushes to teleport everyone away saying that that is their opportunity to act.

Finally, in Camelot, Merlin tells her companions that they must reunite all the prisoners that Zeldris let go and return them to Liones. While everyone put the afraid people together for Merlin to teleport them, Elizabeth arrives having scape. Upon everyone reunites, Merlin teleport the Boar Hat again and everyone decides to stop Meliodas to become the Demon King.

Right when Elizabeth and the Sins are back to Liones, they are greeted by Bartra, who thanks them for saving the hostages. When this one ask about the others, Merlin tell him that Gowther is recovering of his wounds and that Meliodas and Ban are absent for their own reasons. When the Four Archangels also arrive and offer to form an alliance with Liones and the Seven Deadly Sins, Merlin declares that they will follow Elizabeth's decision, affirming that she is now their leader. Being unable to save Meliodas on her own, Elizabeth officially creates the alliance with the Four Archangels.

The next day, Merlin was helping Gowther to recover by fixing his body. While examining his body parts, Merlin praises her former teacher, admitting that even when she was thinking of make some upgrades on him, Gowther is so well built that it is no more room for improvements. There, Gowther's head ask Merlin for a favor. Merlin states that she can't make any improvement on him, leaving Gowther to recite a phrase that his creator used to say to express his admiration for Merlin's talent. Merlin accede to listen his petition but with no guarantees. Upon hearing Gowther, Merlin reacts surprised by his request, asking if what Gowther had not been able to say previously about its creator ending the Holy War was related.

Later, Merlin meets with Elizabeth and the other Sins to tell them that she decided to go to Camelot on her own to rescue Arthur. King and Diane tell her that they should wait to be able to go along with Stigma's entire army, but Merlin says that upon noticing their march towards them, the demons would only reinforce their defenses, so it is best to look for Arthur at that moment. Escanor is opposed to her plans stating that it is not worth that she is put in danger by a simple child like Arthur, causing Merlin to give him a furious look. When Hawk asks Merlin why she's going so far to save Arthur when he's not even woken up to his magical power, Merlin reveals that Arthur is a hoping child chosen by the holy sword Excalibur to lead Britannia someday. Although surprised by it, Hawk says that even having the holy sword Arthur is unable to defeat Meliodas and the other demons on his own. Merlin does not answer, be aware that his words are true.

In that, Merlin receives a telepathic message from Cath, telling her that Arthur is about to be killed. Merlin immediately teleports to Camelot, where Arthur was about to be defeated by Cusack. After surprisingly appearing before the demon, Merlin uses Icicle Castle to immobilize Cusack while taking Arthur in her arms. Merlin thanks Arthur for staying alive and also Cath for alerting her to the situation. Meliodas demands Merlin to return the Commandment of Faith, but Merlin tells him that just as he is trying to save his beloved, she and her friends are risking their lives to save him. Just as Cusack manages to break free, Merlin rushes to teleport back to Liones along with Arthur and Cath.

Diane reproaches Merlin for taking that risk by going to Camelot, Merlin says that what matters is that she and Arthur could return safe and sound. Merlin asks Elizabeth to take care of Arthur's injuries, however, Arthur falls under the effects of Cusack's Resonant. After taking Excalibur, Arthur is forced to stick it in his heart, to the horror of Merlin and the other Sins. Merlin is desperate at the demise of Arthur, begging Elizabeth to cure him but this is impossible if Excalibur is not removed. She tries to make him release the sword, but it is impossible.

New Holy War arc
After not being able to save Arthur, Merlin is devastated before its body still crossed by Excalibur. Merlin says that Arthur was a brilliant young man with a magic still unknown inside him, and she reproaches herself for not being able to take out his latent potential afloat, wondering if Arthur was saved from having achieved it. Not knowing if the soul of Arthur left or if it was absorbed by the Excalibur that is already looking for its next owner. Merlin says that after living such a long life, she no longer knows what to feel or think at such a moment, and that all he can see around her is darkness Elizabeth kisses her on the forehead to comfort her, apologizing for not having anything to say to make her feel better. Merlin remembers that little "spell" that Elizabeth used to comfort her as a child.

Recovering, Merlin leaves to the castle next to Elizabeth and Escanor to the meeting of the alliance to decide the strategy for the Holy War. Merlin claims that at all costs prevent Meliodas from becoming the Demon King and free Elizabeth from her curse, but above all will no longer allow losing another person prized for her.

Merlin directs the meeting attended by the Four Archangels and the Holy Knights, deciding what will be the formation for the battle. When Escanor enters into a small argument with Sariel and Tarmiel, Merlin demands silence from them. There, she explains that the forces will be divided into three groups: the "Defensive Force" that will protect Liones from the demons, the "Search-and-Destroy Force" that will advance towards Camelot and face the Demon Clan army directly and the "Assault Force" that infiltrated Camelot to execute a direct attack. Merlin states that the Assault Squad will be conformed by herself, Ludociel and Escanor, in order to avoid being affected by Zeldris' Piety. Once the formation is decided, everyone goes to prepare.

Merlin is in charge of creating special costumes for her and the Deadly Sins to allow them a better performance in combat and ability to regenerate if they break. Merlin has a little conversation with Elizabeth, saying that even when she said before that the awakening of Elizabeth and Arthur's power were vital for that battle, she was not completely honest, since that means that Elizabeth's curse take effect. Then, Merlin says that they must reliant on Elizabeth's power and that she must survive.

When the Assault Force arrive at Camelot, they discover the castle covered by an enormous sphere of darkness, a product of Meliodas' fusion with the Commandments. Merlin asks Ludociel for an idea to enter. Ludociel invokes his Sanctuary, creating an Ark barrier around him, Merlin, Escanor, Hendrickson and Gilthunder, being able to enter into the space of darkness thanks to Merlin's Commandment that wants to enter and join the others. Ludociel declares that once inside they can not leave until they kill the creator of the dark field, Meliodas. However, Merlin declares that there is another way: returning Meliodas to normal.

Upon entering they find the cocoon of where Meliodas is in. The five are received by Zeldris, Cusack and Chandler. Merlin personally confronts Cusack. When the battle begins, Merlin watches as Escanor attacks Meliodas' cocoon, and while the demons are distracted, assaults them with Double Impact. When they emerge unscathed and attack her, she notes that Chandler and Cusack's power far exceeds that of the Ten Commandments. Escanor moves to protect her but is thrown back by the two demons' combined attack, forcing Merlin to repel them with the second stage of her spell, saying that the important thing is to find the way to take Meliodas back, not the numbers.

After Ludociel attacks Chandler and Cusack, and confronts Zeldris, Merlin declares that although the numbers do not matter in that situation, the power of Ludociel was essential to get there.

When Zeldris releases his original magical power, Ominous Nebula, all present are attracted to him by a great force, then being repelled and wounded by a strange force. However, Merlin manages to stay safe by teleporting over and over, taking care of keeping Hendrickson and Gilthunder out of Zeldris' range the same way, a feat made possible by her infinite magical power.

Merlin is annoyed when Ludociel and Escanor argue in the middle of the battle.

Ludociel asks Merlin for the identity of Zeldris' power, leading Merlin to explain how the Ominous Nebula has three characteristics: the ability to draw things towards Zeldris as its center with an incredible power of attraction, including only living beings and that no physical attack manages to reach it, being them hit by an unknown attack instead. Merlin points out that none of the magical attacks that she and Ludociel used previously affected Zeldris, which must be due to the powers of the Demon King. Merlin declares that Zeldris has an attack from which it is impossible to defend himself and on top of that resistance to both physical and magical attacks, which will make the battle harder than they could have imagined.

After Escanor refuses to obey Ludociel and this ended up being attracted by Zeldris, Merlin asks him to help him, to which Escanor obeys catching Ludociel and agreeing to help him fight.

Merlin is surprised when the combination of Escanor and Ludociel fails to overcome Zeldris' ability. There, Merlin notices how the power and speed of the vacuum created by Zeldris increases, attracting her with such speed that it prevents her from teleporting in time to evade the blow of Zeldris who intends to take away the Commandment. However, Escanor shields Merlin with his body taking almost all the attack. When Merlin loses consciousness by the blow, Escanor releases his Crazy Prominence in his anger.

Seeing how Zeldris manages to avoid the attack, as well as destroy a huge debris that falls on him, Merlin finishes deciphering the true nature of the Ominous Nebula, calling it so simple an yet unparalleled in its brutality. Zeldris is not depend of his sight, hearing or sense of presence, since his power is a technique of extreme concentration were Zeldris rotates his darkness at immense speeds, creating a vortex that surrounds and attracts all living beings around him. This power makes the air flow and creates a vacuum and everything that comes in contact with it is sliced at a god-like speed by pure reflexes. Merlin end naming it a Full React.

As Escanor decides to fight Zeldris, he ask Merlin to hold on for a minute. Merlin says the she is done with mistakes and uses Cho-renzoku Teleport to acquire te enough speed to teleport herself and Hendrickson out of Zeldris' power. When Escanor manages to break the Ominous Nebula, Hendrickson and Merlin witness how he manages to hurt Zeldris and leave him at the mercy of Ludociel after being returned to his night form when Chandler creates an artifical night.

When Ludociel manages to hurt Zeldris with his Gold Shining, he takes the heat in a fight with Cusack. There, Chandler decides to take charge himself of Merlin and the others. Escanor asks Merlin if Chandler and Cusack are as strong as they say, leading Merlin to tell that both with the older demons alive, owners of a terrible power and the teachers of Meliodas and Zeldris who were always with them. However, both rarely participated in the old Holy War, leaving much of themselves in mystery.

As Chandler and Merlin decide to start their battle, Merlin fires her Exterminate Ray, to which Chandler responds with the same spell. However, Chandler's Exterminate Ray is much larger and more powerful than Merlin's. As the two attacks collide, Merlin tells Escanor to look for the opportunity to take Rhitta, although he sees none. When Chandler's  Exterminate Ray begins to take the upper hand, Merlin uses Enchant: Infinity so that her attack grows with infinite magical power, surpassing Chandler and achieving to hit him.

When pushed back with several wounds, Ludociel asks Merlin why nothing he does has any effect on the two demons, wondering if it is because of their magical powers. Merlin reveals that at some point in the past, Chandler and Cusack sealed their original magical powers for some reason, but even so they continued to be considered the most powerful demons after the Demon King just for being strong, fast and hard as anyone else.

Escanor asks if they have no weaknesses, Merlin agreeing that they do not. However, Merlin says that it is only necessary to create some. Chandler and Cusack initially does not believe Merlin's words about creating weaknesses in them, claiming that none of her attacks have the slightest effect. However, Chandler is suddenly assaulted by a lightning strike, at the same time that Cusack is hit by a wind concentration. both are surprised at the damage that those attacks caused them. Merlin goes on to reveal that it is the Double Impact she used previously, which is actually an attack combines the magical attributes of the four elements and multiplies it, which allowed Merlin to discover which elements were most vulnerable, being for Chandler the lightning and for Cusack the wind. Also, the second weave of the Double Impact is a spell that decreases the resistance of the opponent and thanks to her Infinity, the resistance of both will continue to decrease with each attack.

Chandler tries to use Absolute Cancel to undo Merlin's magic, but before he can do so he is assaulted by another lightning attack, injuring himself more than with the previous one. While trying to perceive from where the attacks are coming from, Cusack receives another attack. Merlin reveals that her Infinity causes endless and untraceable magical powers of lightning and wind to continue dancing and reacting to every movement or magical invocation they make, assaulting them until they die. Ludociel asks what kind of bizarre magic it is, with Merlin claiming that she does not understand it well either; she took a dual element attack magic, attributing it "invisibility", "undetectability", "automatic tracking" and on top of that, she casted Infinity. Escanor asks her when she came up with all this, and she reveals that she thought about it while using teleportation to escape from Zeldris' Ominous Nebula.

As Chandler and Cusack continue to be stricken by attacks, Cusack refuses to accept that the most powerful demons are being humiliated by a mere human. Then he manages to use Resonant, the signature move that gave him the "Napping Reaper" moniker, on Merlin. Getting inside Merlin's subconsciousness, he sees her true appearance. Cusack mockingly threatens her saying that she will suffer the same fate as Arthur, but not before she nullifies her barricade of attacks. Cusack claims that she will lament in hell for opposing the most powerful demons, when suddenly receives a single punch in the face. Merlin, free of any control, tells him that it was foolish of him to think that she could be taken over, reminding the demon that she got the blessing of the Supreme Deity, on top of the strengthening of her soul and spirit as well. Merlin menacingly claims that Cusack will feel all of Arthur's resentment.

Cusack's soul begins to be slowly tortured by Merlin's consciousness, who mutilates him with snake-like creatures. Merlin praises his resistance to so much pain that it would have destroyed the mind of any other demon, saying that it would be problematic if it were otherwise. Merlin declares that the only way she can fill her heart after losing Arthur is inflicting torment and agony on Cusack, and mutilating his soul until the point where he can no longer return to normal.

When the spell that Gowther had used 3,000 years ago began to fall apart due to Meliodas and the Demon King discovered the truth, Merlin, like all those who were under its influence, begin to suffer the effects of the spell that kept their memories altered. Thus, Merlin realizes that "Estarossa" was actually the Archangel Mael. While Merlin suffers the stress of the spell breaking, Cusack takes the opportunity to escape from her mind.

When Escanor worries about Merlin, she tells him to take the opportunity to take Rhitta. Thanks to this, Escanor resumes his daily form, which relieves Merlin. However, it is alarmed that Cusack, Chandler and Zeldris managed to recover completely.

While Hendrickson and Gilthunder believe that the state of Ludociel is due to the demons, Merlin explains that it is actually the spell of her former master, quickly deduced how he use black magic to alter all the memories about Mael and turn it into "Estarossa", even for the Demon King. Knowing that the impact of the truth in their souls causes a great conmosion, the bigger the closer a person was to Mael, Merlin wonders why Zeldris does not suffer any effect. Zeldris explains that it is because he never looked up at Estarossa as a brother, in fact feeling relieved to discover that he really was not.

When Chandler and Cusack decide to join in their original form, talking about a demon called the "Original Demon" who was punished by the Demon King when trying to dethrone him and divided into two teachers for his children, Merlin is surprised and terrified to feel the magic power that both begin to form. When his fusion is complete, Merlin observes incredulously how the field of darkness created by Meliodas and the Commandments dissipates. There, the Original Demon appears, and Merlin declares that they have lost every chance of victory.

The Original Demons stars a fierce fight against Escanor. When this one receives a big slash in his chest after their clash, the Original Demon points that is a pity that Escanor is no longer on his top. Escanor then uses his Cruel Sun, engulfing the Original Demon. Merlin claims the the only thing they can do is survive until the arrive of the reinforcements, Escanor insists that the two of them are enough to deal with it, but the Original Demon emerges having blocking the attack with his shield, claming that their deaths are already decided. Merlin there attacks him with Exterminate Ray, but the Original Demon easily counter it with his energy breath and then gives Escanor a serious damage with a kick of his back legs. However, before he can finish Escanor, a enormous flying object comes to the scene, astonishing Merlin when it is revealed to be Chastiefol, that deals a huge hit on the Original Demon.

Merlin recognizes that King must be controlling Chastiefol from far distance, indicating that his true power as Fairy King must awake and have and incredible evolution. As Chastiefol assumes its Fourth Form, Merlin teleports herself and Escanor away avoiding the terrible explosion that it release on the Original Demon, leaving Merlin astonished with its destructive power.

As Zeldris is able to use God to cancel Chastiefol attack on the Original Demon, this one reassumes his fight with Escanor and Merlin while Zeldris deals with Chastiefol.

Suddenly, Merlin notices Melascula's test tube glowing, realizing that her Commandment must be reacting to something. As the test tube shatter, Melascula's Commandment leaves her body and joins the other four that appear to be absorbed by Meliodas' cocoon.

While everyone resigns themselves to the Commandments being absorbed, Merlin exclaims that it is far too soon to surrender. There, she begins to make incantations and a magical seal in the shape of a clock appears before her. Zeldris and the Original Demon recognize with disbelief that she intends to use Chrono Coffin, a forbidden art to suspend the cocoon in time. The two attack her in order to stop her, but are stopped by King and Escanor, Merlin asks them to resist enough for her to complete the spell. As Escanor is defeated, the Original Demon pretends to end with Merlin. However, before he could kill Merlin, the Original Demon is restrained by Ludociel who uses Ark to hold on his weapons.

As Ludociel fights the Original Demon, Merlin continues with her spell, lasting ten minutes for it completation, and Merlin ask for Meliodas do not awake until then. As Merlin is knocked down by Ludociel being pushed back, Merlin warns him to stop attacking, having sensed that the magical power of the Original Demon allows him to increase his power as his life is shaved. As she reassumes her incantations, Merlin fears that if his power keeps powering up at such pace, it will be impossible for them to hold out.

After the inrush of Mael, who uses his newly borrowed Sunshine to stop the Original Demon and undo his Darkness spell, Zeldris takes the opportunity to attack Merlin with his dark matter, dividing it into several dark creatures to evade Ludociel's Ark barrier. However, Elizabeth and the Sins manage to protect her, leaving Merlin five minutes to complete the Chrono Coffin.

Mael is able to fight Zeldris the next two minutes, but this one manages to overcome him and release a barrage over Merlin and the others. However, King uses True Pollen Garden to protect everyone, despite Zeldris keeping attacking under desperation of Merlin only lasting one more minute. After Mael defeats Zeldris, Merlin complets the Chrono Coffin and leaves the cocoon suspended in time. While everyone celebreates the end of the Holy War, Merlin is debilitated for the incantation of the Chrono Coffin, saying that will need a lot of booze from Meliodas to recover. However, when Hawk discover that the cocoon was already empty, Merlin 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, and also creates one for Hawk. Merlin warns Diane and King that magical attacks doesn't work on the Demon King, but any of them is able to make a threat for the Demon King, who easily incapacitates everyone including Merlin.

When Ban saves Hawk from being killed, Merlin shows happy of know that he was able to return from the Purgatory.

As the Demon King releases a toxic and caustic storm over the area, Merlin and the Sins are protected by King's True Pollen Garden.

Seeing Ban fight against the Demon King, Escanor is surprised by this one by surpassed by Ban, and Merlin points him that Meliodas is helping fighting from the inside, claming that he is not the kind of guy who gives up that easily. When the Demon King manages to take the upper hand, King wonders if the Demon King's power was increased. The Demon King says that their voices could never reach the real Meliodas. There, Gowther comes out with a plan and manages to use his Invasion and take Elizabeth and the other Sins into the spiritual world where Meliodas confronts the Demon King.

As Meliodas can not believe that they are there, Merlin assures him that he is not dreaming, they are there in flesh and bones, or actually in spiritual bodies. Merlin 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. Merlin states that he fails in save Elizabeth, she wil make him fulfill the little promise they did in he past, leaving both Meliodas an Escanor worried.

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, being distracted by Hawk and his 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
The day after the end of the Holy War, Merlin 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, Merlin remains with Elizabeth, Diane and Elaine while the men goes for food in the forest. Merlin notices that Elaine is some plate and tries to change the topic when Diane starts to talk about their future children. As Diane finally breaks down in tears not wanting it to be true that Meliodas is going to leave them, Merlin tries to tell the truth to Elizabeth. 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 dissapear 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 Liones, 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. Merlin deducts that Meliodas is going to break the seal that she put on the vampire Gelda 12 years ago.

Upon returning to Liones, Merlin 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. Merlin is the only one that remains calm 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, Merlin reminds him how he saves a lot of people, including herself. 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. Meliodas reproaches Merlin for putting the entrance in such a remote place, to which Merlin tells him that it is the closest point of contact with the Demon Realm and that she could not put it in the middle of the capital because of the risk of someone else falling into it. 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, 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. Meliodas then asks her if she closed the entrance to the Demon Realm to what Merlin assures that it will soon cease to exist and that anyway, with the entrance being just the size for a person to pass, not even the White Demons could cross it easily. There, everyone feels that the entrance to the Demon Realm is being opened again to which Merlin recognizes is to invoke an fearesome 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.

In the center of Britannia, the Sins face the giant Indura that was summoned and Merlin see that it reacts to their intention of kill him. When the Indura accumulates a bulbing in his tail and then release a big object from his tail that explotes and scatter in multitude of small objects, King wonders if that are some kind of spores, but realizes that they are too big for that. 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. Merlin uses Exterminate Ray to eliminate so many babies as she can.

When Ban tries to use his Fox Hunt, Merlin teleports Courechouse and returns it to him, telling him that with his current capabilities, he should be able to get even more power than before if he uses it.

Merlin and King continue to eliminate all the babies they can, but they disperse too quickly and far enough for them to reach everyone. 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 wielding his Sacred Treasure, which Merlin confirms. Merlin pass to explain how Courechouse can display attacks in any angle and distance and in top of that have its special power Super Concentration that makes Ban reach the pinacle of his physical and mental state.

Using his recently recovered Courechouse, Ban manages to eliminate thousands of Indura babies with an incredibly extended and powerful Assault Hunt. Upon witnessing it, Merlin says that Ban is already beyond human level.

The Indura then launches the attack, but the Sins manage to finish it with the combination of their attacks. Merlin uses Shock Stinger to attack the Indura.

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, Merlin ask if he really expect that they did not notice that he was in trouble.

Meliodas angrily says that it is not their fight and order them to return, but all the Sins express their desire of help. As Meliodas says that the Demon King is stronger than the last time, Merlin affirms that she have already fooled both gods once, so now killing one sounds good.

When the Demon King stands and uses the Indura's heads in his own attack, Merlin quickly teleports the heads behind the Demon King, resulting in this one being hitted by the attack. However, the Demon King receives no damage thanks to The Ruler, which impress Merlin.

Knowing the inversion nature of the Demon King's power, Elizabeth uses Invigorate hoping to that its healing turns into damage. The Demon King then switch off his power, but Merlin launch a magic blast hidden behind Elizabeth's technique, catching the Demon King in a fiery explosion. Elizabeth praises Merlin, to which she says that she is good too.

As the Demon King is taking back, 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.

Fortunately, Escanor arrives now again with his magical power within him. As he joins the fight, Gowther takes the chance to take Meliodas inside Zeldris and the Demon King's spiritual world. Meanwile, Merlin uses a Perfect Cube to guard Elizabeth, Diane and the bodies of Gowther and Meliodas.

When King, Ban and Escanor are wounded by the Demon King, Elizabeth ask Merlin to release her Perfect Cube. Even with the risk of her curse, Merlin do it and Elizabeth uses Invigorate to heal the three fighters. As the battle goes worse do to the Demon King 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 Merlin 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.

When Diane uses her Mother Creation against the Demon 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 Meliodas declares that their mission to end the Demon King will begin.

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.

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 lmit. 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 beginning to take over every living being, rock and hill. Merlin deduces that with both Meliodas and Zeldris have rejecting him, the Demon King pretends to turn the very ground of Britannia into his vessel. Thus, the Demon King stands with a new, gigantic and monstrous vessel created from the same land of Britannia.

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 make a completely confident face. The Demon King demands to know why they have that expression on their faces. Merlin points out that his body is breaking asking if that is the best he could achieve with a substitute vessel taken out at the moment.

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. However, Merlin uses Power Limit Break, 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. The Demon King react angry against Merlin as she fools him in the past, to which Merlin says that he should not have gotten in her way.

The Sins then launch their strongest techniques that Melin combines in a single powerful attack using Power Full Conversion. The Demon King believes that his power The Ruler will protect him, but Merlin reveals that the Kill Switch that Gowther has 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.

As Meliodas and his clones use Full Counter in the combined attack to rise its power, Meliodas asks Merlin if the angle of attack is good to which Merlin gives her approval. Meliodas sends the attack to the Demon King killing him once and for all.

Meliodas is asked for Zeldris about how did he make the combined attack with enough power to destroy Britannia but affected only the Demon King. Meliodas then shows him the water bolb that remains from Lake Salisbury, which has absorbed all the excess of power from their attack. Zeldris says that is impressive that he was able to make that call so quickly, but Meliodas explains that it was Merlin who did it.

Diane then calls for Meliodas to show that the Commandments are still there. Merlin explains that despite them defeating the Demon King, his power could revive after decades or centuries, but that there is a way to completely destroy him. Meliodas then releases his original magic power which impresses Zeldris with his power level that even surpass their father. Meliodas then pretends to thrown all his power to the Commandments to completely destroy them along the Demon King.

While Escanor begins to reach the end of his life, he gives his farewells to everyone. Finally, Escanor confesses to Merlin that he always loved her. Not only for reminding Rosa, but because she looked at him, spoke and connected with him without any prejudice or discrimination. Merlin says he gives her too much credit because in the end, she only found him fascinating and only saw him as a test subject. However, Escanor states that is more than enough to be happy because it means that he could exist in some corner of her heart.

Affected, Merlin says it's too late for everything and that she wishes Escanor had met her 3,000 years ago. Escanor tells her that he will be with her no matter what decisions she made, what crimes she committed or sins charged. Surprised, Merlin asks if she knows about her sin. Escanor admits that it's just a feeling because she has always had that sad look in her eyes since they met.

Escanor's body begins to burn and warns everyone that they should walk away, but everyone wants to see him leave. Merlin then approaches and to everyone's surprise, kisses Escanor burning herself in the process. Merlin tells him that she will never be able to reciprocate his feelings for her, but that as proof of his existence, she will keep those burns as a symbol of the only man who has loved her.

Current 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.

When Diane happily states that all the Sins have achieved their goals, she ends up realizing that she never knew what Merlin's goal was since she never talked to them about it. Ban stress that she could not have been working with Melidoas for 3,000 years without expecting obtain something 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 and Hawk Mama in front of the orb of water that used to be the lake. Merlin then says it is time to start, when Meliodas asks her what, Merlin surprises everyone by declaring that she refers to Arthur's awakening.

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 set 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. 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 does not understand, that his body hurts and asks for help. Merlin limits to say that when the king awakens, he will release the seal on chaos and chaos will return home to the king. 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. Arthur, wrapped in great darkness, laments the fact that Meliodas betrayed him. There, Merlin hugs him and tells him that Meliodas did not betray him and that he should not let his powers consume him.

Arthur then manages to calm down and reality returns to normal. Merlin tells him that the Melidoas of that time was not the real one, Arthur insists that he betrayed everyone, but Merlin explains that he misunderstood him and that as proof is the fact that the Sins and Elizabeth are there with him.

Meliodas then asks Merlin what she did to Arthur and what she 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. Arthur tells Merlin that he did not know he had such a terrible past, to which Merlin tells him it was a long time ago. Merlin remains silent and serious throughout the rest of the story, until 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 does not 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 also 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. Gowther is sad to confirm that what the Lady of the Lake told them is true

Meliodas tells Merlin to look him in the eye and asks if she really tried to kill Elizabeth. Merlin replies that since Meliodas' only objective was to break Elizabeth's curse, he could have abandoned the mission of destroying the Demon King after he had accomplished it, something she could not allow. Meliodas exclaims furiously that if she reactivated the curse for that reason, to which Merlin replies that she also saved Elizabeth. Meliodas then asks if forming the Seven Deadly Sins was also only in search of her goal, to which Merlin does not respond. The Lady of the Lake mentions that hating someone until she wants to kill him but at the same time being able to love him is what human beings do, so she wonders if since they and Merlin are of different races, they will ever really be able to understand each other.

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 no one 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.

Hawk Mama then deflates, with King revealing that she was never a pig but a shell made of multiple layers of moss. Arthur asks where the content is, to which Merlin reveals that he is inside him from the moment he opened his eyes as the King of Chaos. Arthur asks surprised if the huge pig is inside his body, to which Merlin corrects that Chaos is what is inside him. Understanding that the strange magic that Arthur unconsciously used was Chaos, Meliodas asks Merlin to return Arthur to normal, to which Merlin replies that it is impossible given that Chaos has chosen to coexist within Arthur which proves that he is the true King of Chaos. Meliodas asks her what about Arthur's will to which Merlin says he can blame her for everything he wants.

Arthur then asks them to stop arguing. As Arthur begins to talk about his feelings for the Sins and Merlin, his magic begins to alter reality again. When Arthur says how Merlin told him to become a king to make the impossible possible and create a world where he can keep his loved ones, he ends up realizing what he did with his surroundings.

Cath then leaves the Boar Hat happy to see Arthur. However, the Lady of the Lake is alarmed by its presence and tells Merlin not to let it approach Arthur. As Cath ends up wanting to devour Arthur and he is saved by Meliodas, Merlin is alarmed to see Cath tear Arthur's arm.

Merlin ask the Lady of the Lake if she knew Cath's true colors. After the Lady of the Lake reveals his true identity as the monster Cath Palug, Arthur asks Cath to stop since there must be a good reason for what he is doing since he protected him with his life. However, Cath Palug reveals that he only did so that Arthur could awaken as the King of Chaos, since he would not have had a good taste by devouring him otherwise. 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 and the Sins in it.

Merlin tries to use Exterminate Ray to stop being sucked, but is useless. There, Arthur destroys the dimension with a reincarnated Excalibur. Cath Palug is amazed and asks Arthur to let him eat every part of him. Arthur says that upon hearing that, he feels he can kill him without any regret. When Cath Palug throws himself at him, Arthur cuts him with Excalibur, apparently destroying his body in pieces. He then 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 or let them involved into that for her selfishness. Merlin says that this is the path she chose and hugs Arthur saying that she will protect him with her life.