Dead Mount Death Play

Dead Mount Death Play is a reverse-isekai action-fantasy anime (based on the manga by Ryohgo Narita, known for Baccano! and Durarara!!) with two cours/seasons.

In a fantasy world, a legendary hero called the Calamity Crusher confronts and seemingly defeats a powerful necromancer known as the Corpse God. In his final moments, the Corpse God casts a reincarnation spell to escape death.

Instead of returning to his own world or allies, he awakens in modern-day Tokyo (specifically Shinjuku), possessing the freshly murdered body of a teenage boy named Polka Shinoyama, who was just killed by an assassin.

The Corpse God, now living as "Polka," simply wants a quiet, peaceful life in this strange new world full of technology and no magic (at first glance). But that's easier said than done, he quickly gets tangled in the criminal underworld, attracts assassins still targeting the original Polka, draws the attention of police and eccentric characters, and deals with various factions, conspiracies, and even connections from his old world spilling over.

It's packed with a large ensemble cast, mystery, action, dark humor, urban chaos, and that signature Narita style of interconnected characters and escalating weirdness. Think The Devil is a Part-Timer vibes but darker and more ensemble-driven.

If you're into reverse-isekai, necromancy powers in modern settings, or chaotic group dynamics, it's a fun (and often underrated) watch!