MTL - The Life of a Villain Starting From Naruto - Chapter 124 so the answer is

Three years ago, the animals and plants on Earth underwent crazy and unexplainable changes that included transformations, reversions, and the addition of otherworldly species. And it was the start of a brand-new type of profession in the new generation of humanity – Monster Trainers, people who specialized in taming monsters.

On his 18th birthday, the protagonist of the story, Gao Peng, suddenly received the ability of being able to see the attribute data frame of monsters. With his ability, he aspired to become the strongest monster trainer that ever lived while looking for a method to revive his parents!

- Description from Novelupdates

This is not your usual isekai novel. it has my unique world background, unique power system and i am trying it make it a unique experience for every reader. :)

Athan, a 16-year-old boy, lived until he was killed for a stupid reason. (stupid reason & more in the prologue:v)

But it seems that fate had stored different things for him as after death as he transmigrated in the magical world inside a dead body of a boy with the same name and same facial features as him.

He also found out that a mysterious black whirlpool seemed to be inside him.

Was someone responsible for his transmigration? if so then who? and why? or was it pure coincidence that he got a new chance at life?

In a world shadowed by death, the silent realms await, home to the undead and the Grim Reaper's sanctuary. As long as death's presence endures, the great Undead Queen will return.