The TV anime is based on the manga series, which is based on the light novel series.
The official website for Tensei shitara Slime Datta Ken TV anime announced a sequel on Sunday.
Micro magazine has been releasing the light novel series with illustrations by Mitz Vah since 2014, and thirteen volumes have been released as of September 2018.
Fuse has been writing the story on the Shousetsuka ni Narou website between 2013 and 2015.