That Time I Got Reincarnated as a Slime (Japanese: 転生したらスライムだった件 Hepburn: Tensei Shitara Suraimu Datta Ken) is a Japanese fantasy light novel series written by Fuse, and illustrated by Mitz Vah. It was serialized online between 2013 and 2016 on the user-generated novel publishing website Shōsetsuka ni Narō. It was acquired by Micro Magazine, who published the first light novel volume in 2014. Fourteen volumes have been released as of March 2019. The light novel has been licensed in North America by Yen Press, who published the first volume in December 2017. It has received a manga adaptation published by Kodansha along a manga spin-off published by Micro Magazine and an anime television series adaptation by Eight Bit.