The Seven Deadly Sins and the Ruler of Death

The Seven Deadly Sins and the Ruler of Death (〈七つの大罪〉と死の支配者) is a collaboration game event in Mass for the Dead with characters from Overlord and The Seven Deadly Sins. It was released on October 1, 2022 to October 15, 2022.

Background
A guest from another world has been recently summoned to the Throne Room. The boy, who calls himself Meliodas, who is not as old as he looks. While being cautious of the mighty magical power hidden in his body, Momonga decides to cooperate in the search for a girl named Elizabeth――

Incident
After a long battle the Seven Deadly Sins go their separate ways. For its captain, Meliodas and Elizabeth the third princess of the Kingdom of Liones, the couple decided that before succeeding the current King Bartra and become the new king and queen, they will first travel around Britannia for their honeymoon to visit the lands of their memories. The couple are in town making preparations browsing through the shops on the streets. Elizabeth before leaving the next day, plans to see her father before heading out with her husband. She feels it is almost unreal that they have reached this point in their lives, wishing to have new memories that they can reflect on after they return from their trip. Meliodas hopes that as long as the peace hold up, then they will not have to make their children fight. This bring to mind about King and Diane children. As Elizabeth ponders, a Crack appears behind her, pulling her through to Meliodas's shock who soon follows after her. The Crack after sucking its victims in, quickly vanishes, its brief emergence unnoticed by the merchants and shoppers, nor realize that it absconded with the royal couple.

In the Throne Room of the Great Tomb of Nazarick, a new summoning experiment is about to be conducted using a Chaos Stone. Momonga who is present calmly observes the Crack embedded in the ground contemplating on the Sea of Possibilities that lies beyond the spatial phenomena. His ruminations are brought back to reality when Demiurge reports that preparations are complete. Noticing his master's interest in the Crack, the Floor Guardian inquires if there is any concern. Momonga merely replies he was thinking about the power on the other side which Demiurge knows its something that can turn ideas into reality and also the cause of many several incidents that plagued Nazarick. Not only that various entities have emerged from the Crack, though are only subordinates to whatever reigns in the Sea of Possibilities. Demiurge cites Shiro to be one such existence, however while the boy claimed to be born from the Sea of Possibilities, his true identity is still unclear as is the nature of the Crack. Hence why they have enacted a new summoning experiment to hopefully extract new information in spite of the dangers.

The experiment is initiated and the Crack glows bringing out Meliodas, landing lightly to the floor who warily. Momonga observing the scene sees that experiment has once again brought an exception into the world, though is surprised that only one person came through. Meliodas then demands then to answer two question. One if they are responsible for summoning him. Momonga clarifies that it was the work of the Crack that brought the boy, though admits that they may have triggered the phenomena. The second question is where is Elizabeth? Momonga cannot answer Meliodas as the boy was the only one that came through the Crack, but offers to help find her for the visitor. After a few tense seconds, Meliodas casually accepts relieved that there is no need to quarrel. This is a bit unexpected as Momonga did not expect the human to take his word at face value. To the contrary, the human doesn't completely trust the undead, but going by logic, if Elizabeth was not being held captive by him, then there would be no need to offer aid. Meliodas introduces himself, giving his title as Captain of the Seven Deadly Sins and owner of the Boar Hat. Likewise Momonga gives his name and introduces him to his domain, before diving into negotiations.

Once the two exchange information about the current situation and their respective worlds, Meliodas is still unsure of where he is as he feels that he is not in the Demon Realm or Celestial Realm. Momonga's appearance while not appearing as a denizen from the Demon Clan causes Meliodas to stay on guard as he while he can't sense sense any magical power from Momonga he feels he is similar to a demon. And based on Momonga's title as Sorcerer King and a Overlord, Meliodas deduces that his host has the traits of someone that "brings death and fear."

On the other hand, Momonga learning from his guest that he originates from a land called Britannia recollects that Round Table Room once mentioned a place with a similar name. Though from the account of Meliodas, it seems that this Britannia is a different Earth where magic exists. He is more concerned about Meliodas as from using [Mana Essence] he can tell that the boy is pretty powerful and that hostility should be avoided. Thus he prioritizes acquiring any new knowledge or technology Meliodas might have, and is glad that right now he knows what his guest seeks. Under the pretense of accidentally summoning Meliodas and his wife, Momonga offers to provide Nazarick's full cooperation. But asks if Meliodas goes outside the tomb, that he be escorted. From this Meliodas accurately guesses that the Great Tomb of Nazarick is a hidden existence to the rest of the world, hence why Momonga wants to monitor him to prevent him from divulging the tomb's location. The Captain of the Seven Sins is fine with that constraint as he admits that he isn't sure he can shake off Momonga's spies and plus he needs a guide. Before going into negotiations for technology exchange, Meliodas asks how can Momonga be sure if Elizabeth is currently in this world. He is then told that there had been other precedents where guests being swallowed by the Crack are either summoned from the Throne Room or in another part of the world. That in mind, Meliodas will put his faith in Momonga for now giving off a smile to the undead. The smile though does little to allay Momonga as even though Meliodas appears as a child, something nags at the Overlord of the boy being a bit off and warns himself not to let his guard down. Still he resolves himself to make concessions to Meliodas by looking for Elizabeth to remain on his guest's good side. Thus, Meliodas, although it was unusual for a guest from another world, without going through a screening process, was immediately allowed to go outside the tomb.

Outside the mausoleum, Aura Bella Fiora and Mare Bello Fiore introduce themselves to Meliodas as his guides/escorts. Meliodas seeing the twins pointy ears mistakes them to be wingless fairies, but is corrected by Aura explaining that they belong to the dark elf race which Meliodas apologizes as he remembers that Momonga had informed him the races of the current world are a bit different than his. Meliodas wishes to depart immediately, but before doing so Aura asks if it is true that the captain can sense magical powers, which should aid in their search. Unfortunately Meliodas cannot sense Elizabeth as he believes she is either too far away or that the current world is too different from his to allow him to work his magical senses. This is a problem as they do not have any clues. Aura though decides that the best course of action would be to go to a place with a lot of people, as hopefully there someone will have sighted Elizabeth. The destination the trio are going is a human city called E-Rantel. Mare warns their guest that the journey will be dangerous as they many encounter Chaos Beast s and monsters on the way. This does not bother Meliodas as Momonga informed him beforehand, and it will give him a good opportunity to show them a bit of his power. Reflecting on what they said about the Chaos Beasts, Meliodas cannot help but feel uneasy but from what heard they are not associated with the Chaos from his world before he sets off with the dark elves.

As Meliodas and the others leave Nazarick, meanwhile in the village of the lizardmen, in a certain Red Eye tent, Elizabeth awakens finding herself in a strange environment. She is greeted by Crusch Lulu who is glad to see that the human is finally awake and asks her condition. Initially surprised by the appearance of her host, Elizabeth expresses her gratitude toward the female lizardman. Crusch explains that the rangers of Green Claw found Elizabeth collapsed in the woods and brought her back to the village. When Elizabeth asks Crusch to relay her thanks to the rangers, Crusch amused jokingly adds that she should be thanking their benefactor, as in a not too distant past normally the lizardmen would have turned a blind eye to a fallen human in the forest. Over a meal, Crusch explains that the lizardmen did not save Elizabeth out of just kindness. Since humans do not venture near their territory, her coming was a bit concerning so her tribe decided it was best to treat her well.

On the road to E-Rantel, Meliodas finishes off a magic caster type Chaos Beast with Full Counter after it attacks him, causing it to be destroyed. The group note that they have been encountering an unusual number of Chaos Beasts on their journey. Even Aura admits that something is weird and wonders if the cycles of Chaos Beasts spawning from the Cracks in various locations overlap with each other. Unknown to Meliodas, various eyes are watching the group's progression to the human city, which include Narberal Gamma from above in the skies, and Momonga from his Mirror of Remote Viewing. Aura who has been observing Meliodas's fighting abilities concedes that he is stronger than expected and urges her traveling companions to continue forward,

Narberal who has been watching the scene from the sky with a [Rabbit's Ear] enhancing her hearing, then uses [Message] to connect to Momonga to give her report on Meliodas. Her report coincides what Momonga had seen from his mirror, though he is wary of the frequency of Chaos Beast encounters. Narberal thinks that it could be the result of the lowly humans dealing with the monsters, as the number of Chaos Beasts have gradually clamed down as the team approach E-Rantel.

Momonga in the Round Table Room considers her words, as he feels it is something more to it than just that, as Meliodas is an irregular existence in their world. He tells the Pleiades maid to be extra careful and vigilant and to report any incidents. He then asks Narberal about her impressions of Meliodas, for which she states that he is not an enemy of the Supreme Being, but when asked by Momonga what they should be wary of Meliodas in terms of ability, Narberal states that the boy's Full Counter as its power to reflect magic attacks is a real threat to magic caster. Momonga agrees as well, though is unsure if the attack is just limited to magic attacks and wonders if physical attacks could rebound, as it was possible Meliodas was bluffing them. In any event Momonga tells Narberal to keep observing their guest as to him Meliodas represents someone who if ever paired to fight him, he would be at a disadvantage as he is not verse in physical attacks. In terms of any weakness they could exploit from Meliodas, Narberal believes that they do not have enough information to make an accurate assessment as Meliodas's opponents so far were just regular weak Chaos Beasts. But the two agree that even though Meliodas is in a hurry to find his Elizabeth, he is hiding his true abilities. That being said Momonga ends the [Message] to allow Narberal to resume her observation.

Albedo and Demiurge are present in the room with Momonga, who asks their opinion of the human. From Demiurge he suggests that if they cannot find a weak point, they should take the initiative to create a weak point. However Momonga is not willing to go with that option, unless the current situation changes drastically. From their impression of Meliodas, using Elizabeth as a hostage would be more risky. The Overlord turns to Albedo to ask Nigredo, who is magically monitoring Meliodas, to use what little energy she has left to search for Elizabeth. He places top priority on continued magical surveillance of Meliodas and to see if the boy has any countermeasures against information magic. Though they have determined that Meliodas has an offensive barrier, it should not be impossible for him to have additional defenses as he comes from another world. Just as Albedo complies, she receives a [Message] from a summon in the field, reporting that further actions are unnecessary as someone name Elizabeth has been found.

Outside the fourth wall of E-Rantel, Meliodas comments on the size of the city and is given some details of the fortress city and the additional defenses that were built. Meliodas wondering why they are dawdling outside the walls and not going into the city to collect information, is informed by Mare that they are waiting for their contacts. The said someone turns out to be the protagonist and Slimeko. The homunculus having done some interviews at the Adventurer's Guild reports that he has collected the most recent information from the city. However his news is disappointing as so far for the past few days though none of the adventurers who were out subjugating Contaminated Beasts and Chaos Beasts nor peddlers from afar have encountered a woman named Elizabeth. Meliodas hearing the report worries that maybe Elizabeth is not within the range of the human cit. Mare argues that it should not be the case as the other guests from other worlds that appeared outside were always close by. Aura is of mind to think that maybe Elizabeth might have been attacked by a monster or something, and asks Meliodas if Elizabeth would be capable of holding her own against a Chaos Beast. She is given the answer that a Chaos Beast would be no problem to "Bloodstain Ellie." The beast tamer suggests that they should head towards the Great Forest of Tob, when she receives a [Message] from Momonga. After listening she informs her comrades that she has some good news and bad news. The good news being is that Elizabeth has been found, though the bad news is that she is in a dangerous situation.

Back at the lizardmen village, Zaryusu Shasha, Shasuryu Shasha and Crusch gather around Elizabeth relate her story of how she came from Britannia. Zaryusu is astonished at hearing about Britannia as it sounds to be a distant land with strange customs compared to what the tribes of the Tob Forest possess. Shasuryu did not fathom that the Cracks reach would extend so far, even if he is ignorant about the outside world. Crusch questions on the kind of magic her land uses, and when Elizabeth informs the lizardmen that she never heard of Tier Magic, this draws shock as the system of magic is most common throughout their land even among different races like humans. Zaryusu admits that being a traveler tier magic was the one common denominator that all races used, even his benefactors were no exception. Still one thing is for sure, Elizabeth came from an unimaginable place, and they are not sure how to help her return. Zaryusu believes that they should has their benefactors as they are interested in all information about the Cracks and will want to be informed of Elizabeth.

The human princess curious about these benefactors asks Zaryusu about them, but before he can go into detail, Zenberu Gugu and Kyuku Zuzu rush into with dire news. Through their heavy breaths the two report that Chaos Beasts are headed towards the village. Not only that their numbers of as far as they can see and appear to be surrounding the village. Shasuryu hearing this demands what have the security team been doing all this time, which Zenberu states he heard this directly from the guards that miasma was pouring from the forest and before they knew it the Chaos Beasts were there. Kyuku urges the chieftain to hurry as a meeting is being held by the warriors as he and Zenberu leave to partake in the defense of the village.

Shasuryu prepares to go out to join the battle as is Zaryusu. The former traveler insists that Crusch and Elizabeth evacuate with the other non-combatant, but Crusch is insistent that she stay and fight too, as they will need the healing powers of a druid. Zaryusu does not have any of that as his wife is at a precarious stage in her pregnancy. At an impasse between Zaryusu concern for Crusch's health and her desire to protect her home, Elizabeth offers to stay and use her healing magic in her place. At first Crusch is unwilling to get Elizabeth involved in the village's matter, but the human girl wants to repay her rescuers and promises to protect her husband during the battle. Touched by the human's bravery, Crusch consents to leave with the other evacuees as Shasuryu begins to mount a defense of the village.

Outside the village, after receiving news from Momonga about Elizabeth's impending danger, the field team immediately flew to the village of the lizardmen. In the air, Narberal guides the team, straddling on Aura's magical beast when she causes them to halt as she detects the presence of multiple enemies ahead using [Rabbit Ear]. Ahead are large flocks of flying type Chaos Beasts and Giant Flying Chaos Beasts. Aura knowing it will be dangerous if they confront them head on direct the team to descend towards the surface. The team lands in the Great Forest of Tob, planning to trek on foot to their destination. All of a sudden they team are surrounded by a massive horde of Chaos Beasts, which includes two Giant Chaos Beasts. The protagonist is stunned by the number of Chaos Beasts as they should have been culled by the ones managing the area. Soon enough Hamsuke, Kyuko and the Death Knight arrive fleeing out from the woods. The trio are relieved at the sight of the team. Glad they are all safe, Aura asks them to explain why the Chaos Beasts in the area are out of control.

The forest denizens report that the miasma from the Crack had suddenly begun leaking out covering the area. After it dissipated, what it left behind was a horde of Chaos Beasts conjuring them seemingly out of thin air. The three outnumbered had been busy trying to fight off the invaders that they did not have time to dispatch a call for help. Aura turning to the protagonist asks him for his assessment of the situation as one anomaly keeps happening on after another. For now the protagonist does not know but feels that whatever is happening may be related to the attack on the lizardmen village. Circumstance currently force the group to hold off from seeking answers but instead fight through the Chaos Beasts. Meliodas then unsheathes his Sacred Treasure to prepare to fight.

By the end of the battle, Meliodas with the aid of two clones of himself defeats the two Giant Chaos Beasts with ease. The protagonist watching the battle end from a distance, observes that the beasts were no match for the human who is way stronger than originally believed. Even if the clones were weaker than the original, depending on the number made, Meliodas's Full Counter potency hasn't diminished and can be fired simultaneously against multiple attacks in all directions. That being said the homunculus NPC likens the attack as an impregnable wall.

Pushing the awe of the human aside, the protagonist asks Meliodas if he can sense Elizabeth through his magic not that they are close to her. Meliodas answers that he cannot which is odd since if Chaos Beasts are attacking her then she should be using magic to allow him to sense her. The protagonist then raises another question, if that he is familiar with some kind of phenomenon that tries to separate them? The question raises an eye from Meliodas, but the homunculus further elaborates pointing out that from his impression, it seems that the Chaos Beasts are only targeting Meliodas and cites the examples of instances that something is determined to keep him and Elizabeth apart. From the massive numbers of Chaos Beasts appearing when he left for E-Rantel, his inability to sense Elizabeth, or that the couple were sent to different locations the moment they were sucked in the same Crack at the same time. Meliodas listening understand the diplomat's reasoning but cannot come to believe what he says is possible. The discussion then takes a turn for Meliodas to explain his history to the protagonist whilst the two fight the Chaos Beasts.

At the lizardmen village, Elizabeth through using Ark successfully manages use Manipulate and Burst to destroy a cluster of Chaos Beasts. When he fight with the monsters is over, she notices that Zaryusu's leg is injured which she attends to and the other chieftains. They lizardmen recognize that she is a far stronger than them and are thankful to the human, as the number or casualties have so far been kept low. More Chaos Beasts keep coming to the village, but the warriors do not falter, and neither does Elizabeth showing a more lion-like personality toward the enemy.

Meanwhile at the Round Table Room, Momonga is in communication with Meliodas. The topic being the issue that the Chaos Beasts aim to keep Meliodas and Elizabeth separated. The news is not surprising to Momonga as Demiurge and Albedo predicted this. Though Momonga requires details of who and why someone would do this to the couple. Meliodas explains what he can that it could be related to a curse by the Demon King and the Supreme Deity placed upon him three thousand years ago. Seeing that Meliodas is his senior, Momonga asks if the curse had been lifted. Meliodas replies that it had been, briefly considering that the revive curse could be Merlin's work but casts the thought away as the mage had no reason to do so. Thinking back the Demon King has long since perished, though the Supreme Deity is still alive, but this curse now seems different compared to the one that the entities placed on him and Elizabeth.

A voice though calls out to him stating this was a revival of a curse, calling him 'son'. Upon hearing the voice, Meliodas freezes as she stares to see a Quadruped Chaos Beast speaking to him. However none of Meliodas companions can hear the Chaos Beast speak. Meliodas then explains that only be can hear it, and that its the voice of his father, the Demon King. This further confounds Momonga on the other end of the [Message] as Meliodas had said that the demon was dead. Meliodas confirms that that Demon King's is indeed suppose to be dead, with his defeat resulting in the end of his land's era of light and darkness. The Demon King then mocks Meliodas, asking if he should be worried about him sneaking about, as opposed to the being who he is talking to, "the ruler of death", which causes Meliodas to have doubts.

Momonga having a direct connection to Meliodas's mind, is able to hear the conversation between the entity and Meliodas wonders if they are truly dealing with the real Demon King. Regardless the entity is still a dangerous existence. Meliodas agrees but its apparent that this Demon King is not willing to give then time to confirm. Momonga then tells Meliodas to handle the entity as he and his subordinates will analyze the situation from behind the scenes which Meliodas allows as he prepares to fight. Using Kami Chigiri, Meliodas kills the Quadruped Chaos Beast, but it matters not as a Warrior Chaos Beast approaches speaking in the voice of the Demon King. The enemy tells Meliodas stating that he cannot be defeated as long as he has another host to possess. Meliodas is annoyed as while he cannot say for sure that this is the real Demon King, which seems weaker than the original, the persistent personality is a dead-ringer for his supposed to be defeated father. Mare also fight is peeved that there are so many in the forest to deal with as his magic cannot encompass so many. Meliodas thinks that his Ruler could defeat them, but the problem is that he doesn't have enough magical energy and that there are too many big and small enemies attacking him. While he can hold on his own, his worries turn to Elizabeth and the lizardmen she is with as he knows that they are not strong enough to last with this amount of opponents. Distracted Meliodas, is hit by a slash attack from the Warrior Chaos Beast, in spite of Aura's warning. The Demon King possessing the Chaos Beast then taunts his son, stating that soon it will be all over as he already found Elizabeth. He informs his son that Elizabeth has been wounded protecting her new found allies, distressing Meliodas.

At the village, Elizabeth took an attack for a lizardman. Despite being wounded, Elizabeth tells them not to worry, but Zaryusu cries out in warning as a Double Sword Chaos Beast looms behind her preparing to strike her. The Warrior Chaos Beast speaking with the voice of the Demon King revels in Meliodas's despair stating his woman's choice to defend others than putting priority on her own life is stupid and now she will die. Momonga listening on the conversation directs his voice to the entity, stating that the human's choice was not wrong stating that the lizardmen are under the protection of Nazarick. Elizabeth's act of kindness will be met by kindness in turn.

Simultaneously just as Elizabeth is about to be killed by the Double Sword Chaos Beast, Cocytus arrives to slay it. His appearance is celebrated by the beleaguered lizardmen as they are now safe with the Floor Guardian present. Sensing this, the Demon King panics, but Momonga announces that he knows that he is not the real Demon King. It is explained to Meliodas that the entity possessing the Chaos Beasts in the area is not Meliodas's father. It is the conclusion among him, Demiurge and Albedo that this Fake Demon King is actually a creation from the Sea of Possibilities. The manifestation of Meliodas's "fear" and "imagination" that was brought to life via the mysterious realm. His subconscious dread of being separated from Elizabeth was brought to life. The Chaos Beast hearing the story of the origin of his existence says it does not matter as Meliodas cannot possibly defeat him as he was born from his fear and he has no Elizabeth of the Seven Deadly Sins to help him. Momonga corrects the imposter Demon King, as Meliodas is not alone. Soon Narberal, Aura, Mare, Slimeko, and the protagonist step in beside the human. Momonga states that while he cannot take the place of Meliodas's "true companions" he can at least give him the strength to thwart this enemy. Hearing Momonga say that causes Meliodas to utter that's what Escanor would have said. Meliodas feeling invigorated at being supported by his allies, faces his fear. The Fake Demon King seeing it can no longer inspire terror at his creator tries to put a brave front but Meliodas is not fooled knowing that the entity will be defeated before the battle ensues.

Aftermath
With the defeat of the Fake Demon King, the Chaos Beasts which were plaguing the Tob Forest vanished. Meliodas and Elizabeth were reunited and decided to spend their reunion in Nazarcik at least until a way was found to return them home.

At the Round Table Room, Momonga is enjoying swapping stories told by Meliodas about Seven Deadly Sin and his guild mates of Ainz Ooal Gown, with both hoping to meet each other's groups one day. Likewise Albedo is speaking to Elizabeth wanting the secret of how to be "touched" by her lover, though the princess tries to avoid the topic. Meliodas seeing how close they gotten over the last few days, confesses to Momonga that when he first laid eyes on the undead, he assumed him to be just as Demon King. But after getting to know Momonga, declares that he is a good king who thinks of his subordinates much like King Batra has much to learn. Momonga learning that Meliodas will become king if he returns to his original world, wonders if they could perhaps develop diplomatic relations with their nations if travel between worlds can be established. Meliodas believes it would be possible as he enjoys their sake. He even says that some of his comrades like Ban would enjoy facing Cocytus or Shalltear Bloodfallen.

A disembodied voice suddenly calls out which both Elizabeth and Meliodas recognize as Merlin. Merlin is relieved to hear that the Grandmaster and Princess Elizabeth are safe as she has been uneased after he felt a huge and strange presence appeared when they vanished. And while Merlin is interested in learning more about the phenomenon which transported them, she warns that the time that the worlds remain connected is brief and will open a portal so that they can return. The stranded couple are disappointed to leave, Elizabeth wishing to says goodbye to the lizardmen for their care for her. However Merlin states it cannot be helped, stating that if the two don't return soon she won't be able to keep appeasing those in Britannia, like Diane and King who have been panicking since their disappearance. Or even Ban who planned on searching Purgatory for them, and Gowther is a nervous wreck without them and not to mention the king who is worried about Hawk being in Purgatory. Meliodas seeing that they must go to alleviate their friends concerns, bides farewell to Momonga and hopes that the undead continues to be a good king. Albedo seeing as she won't be able to know the secret hopes to meet Elizabeth in the future so they could compare notes about each other's legacies. The couple then enter through the gate created by Merlin and vanish.

Momonga ruminating on Meliodas, thinks about the name of his land, Britannia, feeling he heard it somewhere. The Overlord then receives a [Message] from the protagonist who returned from Ashurbanipal who found not just some interesting information on "Britannia" and "Liones" but also "Meliodas" and "Elizabeth" as he distinctly recall the names from memory. When he asks Momonga if he knows about the story of a knight named Tristan, which Momonga to be stunned.

Back in the streets of the royal capital, Meliodas and Elizabeth are happy to be home. Meliodas is eager to go back traveling, but Merlin states that they cannot as they need to clean up the current disaster at the royal castle and urges them to go there. Hearing this the couple realize their honeymoon is postponed until they give an account of their disappearance. Elizabeth then goes to the castle first to put King and Diane's fears at ease. Meliodas is left behind as he thinks about the new friends he made in Nazarick, musing to himself that it would be a good idea to become a king who is admired.