I've Been Killing Slimes for 300 Years and Maxed Out My Level

Synopsis

After dying of overwork in the real world, I’m reincarnated as an immortal witch, and I spend 300 years enjoying a relaxing life. At some point, though, I end up at level 99! All those years spent killing slimes to make the money to pay the bills gave me a ton of experience points. Rumors of the level 99 witch spread, and soon I’m up to my ears in curious adventurers, duelist dragons, and even a monster girl calling me her mom! I’ve never been on an adventure, but I’m the strongest in the world… What’s going to happen to my relaxing life?!

About

I've Been Killing Slimes for 300 Years and Maxed Out My Level premiered on April 10, 2021. It falls under the Animation, Comedy, Sci-Fi & Fantasy genres. The series has aired across 2 seasons and 24 episodes. with each episode running approximately 24 minutes. It airs on AT-X. and concluded its run on June 21, 2025.

Why viewers enjoy I've Been Killing Slimes for 300 Years and Maxed Out My Level

I've Been Killing Slimes for 300 Years and Maxed Out My Level targets fans of Animation anime, especially viewers who appreciate stories that blend Comedy, Sci-Fi & Fantasy elements. This combination of Animation, Comedy, Sci-Fi & Fantasy sets the show's pacing and tone, and explains why it resonates with that specific audience over more general animated programming.

Production

I've Been Killing Slimes for 300 Years and Maxed Out My Level was animated by REVOROOT, Nippon Columbia, Hakuhodo DY Music & Pictures, and broadcast on AT-X.

Critical reception

I've Been Killing Slimes for 300 Years and Maxed Out My Level holds a rating of 7.9 out of 10 based on 238 user reviews on TMDB, a strong score that reflects broad satisfaction from its audience.

Themes & motifs

Recurring motifs and themes throughout I've Been Killing Slimes for 300 Years and Maxed Out My Level include: witch, magic, slime, immortality, reincarnation, slice of life, anime, other world. These threads anchor the show's narrative direction and offer a reliable indicator of the kind of viewing experience it delivers.