Melascula/Plot

Albion arc
After Hendrickson manages to remove the seal, Melascula and the rest of the Ten Commandments appear before the terrified former Great Holy Knight and Fraudrin in Dreyfus' body. She asks Fraudrin why he has a human body, then stating her opinion on humans. After being informed by Fraudrin of the current events in Britannia, Zeldris suggests that they should head for Edinburgh Hill for recuperation of their severely drained magical powers, on which everyone agrees. They fly out of Zhuhur Valley, leaving a terrified Hendrickson.

Arriving at Edinburgh Castle, Melascula and her fellow Ten Commandments find it in ruins and conclude that a powerful magical implosion caused the destruction of the castle; they also find a large hole, which they link to Meliodas. Melascula then tells Zeldris who is trying to figure out why Meliodas caused the destruction, to calm down and relax since its been 3000 years since they were out in the physical world. The Commandments then discuss the destruction of the Albion while Galand decides to attack Camelot. Before Galand leaves, Melascula berates him for acting hasty and thinking with his muscles rather than his brain Later on, the Commandments begin to recover their magical power by consuming the souls of humans, and Melascula summons a Red Demon and Gray Demon to collect souls for them. These two are stopped by the Three Misfits and Hendrickson.

Ravens arc
She is shocked when she senses Meliodas regain his full power at Istar. When Meliodas appears, thanks to Merlin's teleportation magic, she along with the other Commandments, except Galand, are surprised to see him. She watches as Meliodas defeats Galand in five seconds stating that he would be difficult to handle and watches as he warns Zeldris that the Seven Deadly Sins would defeat the Ten Commandments with everything they've got. In response, Zeldris and Fraudrin attack Meliodas from both sides, but he is teleported back.

Melascula appears next to Galand, who is contemplating his revenge, and states that he could not beat Meliodas as he was. Afterword, Zeldris orders them to split up and move across the land to regain their magic faster. Upon hearing this order, Melascula splits off with Galand. It is later shown that she is calling back the souls of the dead to use as her own army of Zombies to wipe out the living humans. Upon sensing that one of the souls she revived was resisting her magic, she and Galand decide to check it out and encounter Ban of the Seven Deadly Sins, who states he will kill them. Angered, Ban picks out his Three-section Staff, but Galand cuts his torso before he could attack. After knowing of the commandment's defeat by Meliodas, Ban comments on their mentioning of Meliodas' relation to the Demon Clan. A furious Galand asks how he's still alive and Ban announces himself as Melascula began to attack on her turn, but Ban avoided her attacks easily. Galand crushes the bandit's head but he recovers from that as well much to their shock. Galand then offers Ban to hit him once in honor of his feats, and Ban prepares his Hunter Fest, robbing Galand of his power and delivering a massive kick to the commandment's gut. Ban continues with his assault on Galand and soon shifts to attempt a hit on Melascula, but she survived using her power. Galand attempts to attack Ban again but fails to land a hit, while Ban counters with his fists. Melascula deduces to Ban's Snatch abilities and warns Galand, Ban continues to provoke them at the other hand.

Although Ban almost wins the battle after he uses Hunter Fest on Melascula and Galand, he finally exhausted. Jericho later carrying Ban and Elaine and flees from Melascula and Galand who give deadly pursuits to them. The two Commandments discovered a bar called "My Sweet Gluttony" inside a dark cave where Ban, Jericho, and Elaine were hiding. The owner of the bar, Escanor became terrified when Galand gets distracted by the booze and immediately commences drinking along Melascula. Admiring how the booze has gotten better over the course of 3000 years, Escanor explains its content which Melascula credits him for knowing much about it. Escanor asks who they are and the due respond that they're the Ten Commandments of the Demon King. Surprised, Escanor is challenged to a Galand game, with each of them delivering a blow to the other and the first one to die loses.

Despite Jericho and Ban's advice, a terrified Escanor accepts the game and is patted in the back by Galand, but the force Galand used caused the secretive sin to pass out. Before they noticed it, morning had already arose, and as Galand attempted to carry the Rhitta, Escanor snatched it from his hand and told him that mere demons cannot hope to wield this axe. A surprised Galand wonders whether he is human or not and Escanor responds that he is indeed human, but he is the very pinnacle of the human species, introducing himself as the The Lion's Sin of Pride, Escanor of the Seven Deadly Sins.

After defeating Galand, a shocked Melascula commends on Escanor's great power, so great Galand broke his own oath and subliminally tried to escape, but was petrified due to breaking his oath while Escanor proceeds to sigh in disappointment. Escanor tells her that if she wants to run away he'd allow her as he still has some chivalry in him, but a she decides to use her Cocoon of Darkness to try and rob Escanor off his soul.

Inside the cocoon she states she is tired of listening to all of Escanor's arrogant talk and asks he be quiet forever, as she removes and devours his soul. However, she is soon struck with intense pain, feeling as if her entire body is on fire. Escanor's soul flies from her mouth and as she is consumed in flames she screams how could his soul contain so much power and what kind of power it is. As Escanor tells her the name of his ability, his soul having returned, she screams in agony as she is consumed in flames, falls over a cliff, and seemingly splits in half when her body strikes a stone ledge on the way down far below.

Great Fight Festival arc
Melascula is revealed to have survived, albeit severely burned, and joins the other Commandments as they race to Drole and Gloxinia's aid in order to confront Meliodas. She remains on the sidelines until Meliodas is rendered powerless by Estarossa. She asks that Gloxinia heal her and then asks Estarossa that she be the one who finishes him off, as retribution for what a member of the Seven Deadly Sins did to her. She begins to remove Meliodas' soul from his body with her Shouraikon spell, but before she can eat it, her neck is snapped and five of her hearts are ripped out by Ban, who unexpectedly reappeared on the scene.

Corand arc
Melascula is revealed to be alive, managing to survive by keeping her last heart and about a month after the death of Meliodas at the hands of Estarossa, was in the strength of the city of Corand creating a dimensional distortion that prevented anyone to approach Camelot. At the root of this, the Seven Deadly Sins went to Corand in order to eliminate this distortion. There, Melascula creates an illusion of Zeldris to attract Meliodas and capture him within her Shadow Cocoon and later to take advantage of the negative energy of this last one to attack the other Sins with revived warriors powered by this energy. Melascula plays with Meliodas' unstable emotions in order to increase his anger and empower her soldiers.

After her soldiers are defeated, the vengeful souls take possession of Diane, and Melascula rejoices for the ensuing fight. However, Diane is saved by Elizabeth and Melascula recognizes her for her goddess persona. After a final word to Meliodas, reminding him that Elizabeth will die, Melascula decides to fight for herself assuming her giant snake form.

She first attacks Ban by catching him between her jaws and although she manages to get rid of Elaine when she tries to save him, the fairy princess' sentiment grows her wings and thus manages to save Ban with her new power.

After Meliodas is released in his Assault Mode, Melascula states that everyone will be killed by him, but Escanor takes care of facing him. Melascula states that without Meliodas and Escanor, the Seven Deadly Sins are not a treat for her. There Ban tries to use Fox Hunt to rip Melascula's last heart, but she prevents it by moving her heart over her body, thus rendering it out of his reach. Melascula manages to seriously injure Ban with her acidic venom, but Elizabeth is able to heal him. Soon, Melascula is easily overpowered by Diane and King being later corned by Elaine and immobilized by Gowther.

Although Elaine insists that they kill her even if it means that she also dies, Elizabeth uses her Tranquilize to remove the miasma from Melascula's body, returning her from her gigantic hooded form to its original form as a harmless little snake. Finally, Melascula attempts to run away but is captured and put into a test tube by Merlin.

Prelude to the New Holy War arc
Later, when Zeldris calls upon the Commandments, Melascula is shown inside Merlin's test tube in her hideout, helplessly hissing as she is unable to respond to him.

Melascula is seen again when Merlin uses her as a bargaining chip with Zeldris, who has come to collect the Commandments. During the bargain, Melascula watches as Merlin explains her past and upbringing. Merlin initially seems to hand Melascula to him, but then encapsulates her in a Perfect Cube to force Zeldris to meet her demands in return. However, as Merlin manages to deceive Zeldirs so that Ludociel attacks him, she escapes along with Melascula and her Commandment.

Melascula is then mentioned again by Zeldris when he tells Meliodas he failed to retrieve her. He says he will still collect her in order for Meliodas to gain the full power needed to become equivalent to the Demon King.

New Holy War arc
As Merlin joins the Assault Force and go to Camelot to face the Demon Clan leaders, she brings Melascula with her, since her Commandment is the only thing that allows them to pass the field of darkness created by Meliodas.

When they were battling Zeldris and the Original Demon, Merlin notices Melascula's test tube begins to shine and finally shatter, as Melascula's Commandment leaves her body and joins the other four Commandments that have been in way to reunite with the five that Meliodas possess.

Chaos in Liones arc
At some point Melascula somehow got her humanoid body back and fell into the service of Arthur Pendragon, who lended her some of his power to became "Chaos Melascula".

Melascula arrives to Liones under disguise but is stopped by some Holy Knights of the kingdom. After revealing herself, she takes out Galand's petrified head and uses the power of Chaos to revive him. Then, both of them declares their intention of killing the Seven Deadly Sins and the Four Knights of the Apocalypse.

Melascula goes after Tristan and traps him with one of her techniques, but Tristan gets free easily using his Goddess powers. Melascula then summons a creature created out of a merging of Demon and Goddesses souls, rending Tristan's holy powers ineffective.

Melascula express her disgust for Tristan for being a Nephilim, the offspring of a Demon and a Goddess, also remarking how similar is the Knight to her mother and how different is from his father, much to Tristan delight. After Lancelot intervention, the brainwashing placed on Melascula starts getting an effect on her, forcing the Demon to turn into her snake form. However, Melascula is easily defeated by Tristan who now was using her Demon powers.

In a last ditch effort, Melascula uses a Chaos Staff to fuse together with Galand, resulting in a powerful abomination capable of resisting the simultaneuos attacks of three of the Four Knights of the Apocalypse.