Collection: That Time I Got Reincarnated as a Slime

That Time I Got Reincarnated as a Slime (Japanese: 転生したらスライムだった件, Tensei Shitara Slime Datta Ken), commonly known as Tensura or Slime Isekai, is a Japanese fantasy isekai anime based on the light novel series written by Fuse. The anime follows the journey of an ordinary Japanese man who dies and is reborn in another world as a low-level monster — a slime — but gradually becomes one of the most powerful beings in the entire fantasy world.

The series stands out among isekai anime because it is not only about becoming stronger through battles. Instead, it focuses heavily on building a nation, creating alliances, diplomacy, friendship, and the dream of creating a peaceful world where humans and monsters can coexist.

The story begins with Satoru Mikami, a 37-year-old office worker living a normal but boring life in Tokyo. One day, while protecting his colleague from an attacker, Satoru is fatally stabbed and dies. However, instead of disappearing, he awakens in a mysterious fantasy world as a small blue slime.

Although becoming a slime seems like the weakest possible start, Satoru receives powerful unique abilities, including Predator, which allows him to absorb creatures and gain their abilities, and Great Sage, an intelligent skill that provides analysis and advice. These abilities allow him to overcome the limitations of his new body and rapidly evolve.

Inside a massive underground cave, he meets Veldora Tempest, one of the most powerful beings in the world: the Storm Dragon who has been sealed away for hundreds of years. Instead of fighting, the two become friends. Veldora gives the slime the name Rimuru Tempest, marking the beginning of Rimuru's new identity and adventure.