"The Final Battle of the Disturbance" (動乱最終決戦 Dōran Saishū Kessen) is the twelfth episode of the Overlord II adaptation. It was broadcasted on March 27, 2018.
As Momon demands to know who his enemy is, Evileye states her name and rank to identify herself as an ally and requests a team up. Reluctant to ask him because of the difference in power to Jaldabaoth, Momon accepts without hesitation. Jaldabaoth and Momon introduce themselves, and by the dialogue, Evileye infers Momon is gathering intelligence on Jaldabaoth. When peaceful resolution cannot be met, the two powerhouses clash, which stirs a heartbeat in Evileye.
As they continue Jaldabaoth uses an aerial attack on Evileye, but Momon steps in to deflect the attack. A small parasite breaches his shoulder plate, but Momon brushes it off as insignificant. Momon takes Evileye- fangirling in his arms- to safety as Jaldabaoth falls back to continue his original objective. The demon warns Momon that should he follow, the demonic flames encircling the sector of the city will be the death of him. When Evileye urges pursuit, Momon argues against it as it would mean fighting seriously against a flying demon with incredible power; which Evileye takes as he is protecting her.
Elsewhere in the Royal Capital, Brain, Climb and Lockmeier escort Tuare from the holding cell, but Brain's instincts have him on edge. When they round a corner, they are trapped by Zero himself, who downs Lockmeier with a punch to his chest. Seeing Brain in person, knowing Succulent was outclassed, Zero offers mercy if Brain kneels and serves Six Arms. Brain deals with Zero but informs Climb and Lockmeier that Tuare is really Succulent using illusion casting. As Brain fights Zero, his blade is deflected by Zero's fists due to the latter's Monk Class. With Succulent using illusion clones, Lockmeier uses an item to reveal the real one so Climb can attack. Climb uses his own martial art he learned from his training with Sebas and overpowers Succulent with a powerful kick to his groin.
Zero, displeased by Succulent's loss, offers a more powered battle with Brain; both use their strongest techniques, but Brain's God Slash and Whistling Wind require him to be still in a circle whereas Zero can punch the air for an attack. As they dialogue, Sebas arrives, shocking Zero who is in disbelief that his subordinates could have lost or the butler getting as far as he did without any damage. Climb informs Sebas the Tuare they found was a fake, but the real Tuare is behind Sebas. Enraged, Zero pauses his battle with Brain to fight Sebas, using his strongest Monk attack to strike Sebas's center mass. Sebas is unfazed, while Brain, Climb and Lockmeier are left speechless by such a powerful fortification from the butler. Sebas nonchalantly counters with a drop heel kick, caving Zero's head in; his dying breath in asking who Sebas really is. In order to relieve suspicion from the trio, Sebas mentions he is "just the slightest bit stronger" and the group moves on.
After Nabe arrives at the manor, Evileye gives a report of their encounter with the insect maid and how she nearly killed her. Both are enraged, but as Entoma survived due to Jaldabaoth's intervention, Momon suggests that the demon arrived because Blue Rose attacked his servant. Evileye in hindsight partly agrees, but as the maid was not as powerful as the demon nor likely aware of the demon's plans, she feels it was still right to battle the insect maid. Momon agrees with her assessment and apologizes. Evileye then internally has the first girlish thoughts she had in centuries since being a vampire.
Momon and Nabe talk in private that, because Demiurge's plan is so precise, the slightest miscommunication could derail everything back to square one. While Nabe is in awe of his planning, in truth Momon only came to the capital by the request of Marquis Raeven to raid Eight Fingers since the reward money was exceptionally high. And since the 'disturbance' was in effect, he would also use the opportunity to boost his own fame. Momon has Nabe message Demiurge as he can't use magic in his suit, and Evileye has her attention mostly on him, thinking it was from his momentary anger from hearing about Entoma. Concluding their talk, Nabe messages Demiurge.
Thinking over the recent events, Momon concludes Evileye is not simply a child with an adamantite ranking. Momon offers to help carry her fallen friends, but Evileye mentions that her team leader Lakyus will be here shortly with her 5th Tier Resurrection Magic 'Raise Dead', but the magic would cause her comrades to be unfit for combat for a time. As Momon would like to meet Lakyus (because of her magic), Evileye gets flustered over the idea (making Momon think she is suspicious); he diffuses the problem that he would like to meet a senior adventurer, leaving Evileye flushed. Nabe points in the distance the Flames of Gehenna standing kilometers tall encircling the city.
As Sebas and the group exit the Eight Fingers base victorious, Climb asks what is Sebas' next move. The butler will take Tuare to a safe location to prevent a repeat of recent events, and promises to repay Climb for what he did today. In the distance, Climb also sees the wall of flames. Everyone in the city of Re-Estize can see the flames, and Princess Renner calls for an emergency summit of adventurers. Lakyus reports the fires to cause no damage, and there are demons on the other side. Renner informs the adventurers of Jaldabaoth and his power- using one attack to kill two adamantite adventurers, making the battle against him all the more difficult. Evileye presents Momon to the summit, as he was able to fight Jaldabaoth on a relatively equal footing; leading Renner to detail her operation. Brain, Climb and Lockmeier join a group to rescue civilians. After the summit, Gazef lends Climb his ring, with the power to boost his abilities, that he was given by Rigrit in the hopes he will return alive.
Zanac and Raeven are with Renner looking at her plan, impressed she will be using adventurers as the brunt of the force while having Momon, Nabe, and Evileye as the arrow to pierce through to the center area to battle Jaldabaoth. But the two-point out that Climb is likely to die; Renner is aware of this as if he does, Lakyus can resurrect him, and in his weakened state Renner can keep him close and in her loving care. In affirmation, Renner shows her true face, disturbing both her brother and the Marquis.
- Evileye falls in love with Momon from watching his fight with Jaldabaoth.
- Momon saves Evileye and battles Jaldabaoth, but the demon escaped.
- Climb and Lockmeier defeats Succulent.
- Brain battles Zero but is interrupted by the arrival of Sebas.
- Sebas effortlessly kills Zero and rescues Tuare.
- Demonic Disturbance begins.
- The gathering of the adventurers of the Royal Capital.
In Order of Appearance
- Ainz Ooal Gown
- Brain Unglaus
- Sebas Tian
- Tuareninya Veyron
- Narberal Gamma
- Lakyus Alvein Dale Aindra
- Gazef Stronoff
- Renner Theiere Chardelon Ryle Vaiself
- Boris Axelson
- Göran Dixgard
- Zanac Valleon Igana Ryle Vaiself
- Elias Brandt Dale Raeven
- There are no new characters introduced during this episode.
- Ability Release
- Iron Skill
- Blade Technique, Whistling Wind
- Single Strike Kill
- Aspect of the Devil: Tentacle Wings
- Flames of Gehenna
- Multiple Vision
- Floating Board
- There are no new locations introduced during this episode.
- Brain didn't say that his ultimate technique was already defeated once, nor that Sebas was the superior monk compared to Zero.
- Jaldabaoth attacks Evileye immediately without telling Momon if he can defend her from his attack.
- The scene of Nabe landing and Evileye reintroducing herself was skipped.
- Momon didn't offer to help Evileye cover the bodies of her friends.
- Momon and Nabe left Evileye to discuss about Demiurge's plan before the Flame of Gehenna appeared.
- Momon didn't ask Evileye from how far away can one cast a resurrection spell.
- Evileye didn't ask Momon anything after hearing him say the Flames of Gehenna.
- Lakyus, Gazef, Princess Renner and the populace of the Royal Capital witness the Flames of Gehenna.
- The scene of Princess Renner explaining the attack plan is skipped.
- Gazef giving Rigrit's Ring to Climb is shown before they depart to rescue the civilians.