Image source: I’ve Been Killing Slimes for 300 Years and Maxed Out My Level volume 18 — via Anime News Network
The 18th compiled book volume of Yusuke Shiba's manga adaptation of Kisetsu Morita's I've Been Killing Slimes for 300 Years and Maxed Out My Level (Slime Taoshite 300-nen, Shiranai Uchi ni Level Max ni Nattemashita) light novel series revealed on Monday that the series will end with the next volume.
Crunchyroll describes the story of the anime:
Shiba's manga adaptation debuted on Square Enix's Gangan Online website in June 2017. Square Enix shipped the 18th volume on Monday.
Morita launched the novel serieson the Shōsetsuka ni Narō website in June 2016. SB Creative publishes the novel volumes with illustrations by Benio in print. The 30th and final volume shipped on June 15.
The novel series ranked at #9 in the 2019 edition of the Kono Light Novel ga Sugoi! guidebook.
The novels inspired a television anime that premiered in April 2021. Crunchyroll streamed the season as it aired in Japan, and it then streamed an English dub for the anime. The second season premiered in April 2025.