That Time I Got Reincarnated as a Slime Novel Volume 9 is written by Fuse with illustrations by Mitz Vah.

The day has finally come for the Tempest Founder's Festival to kick off! From live concerts to incredible feats of monster engineering (and most of all, the massive labyrinth), revelers are sure to have their minds blown. And who should decide to participate in the battle tournament than the hero himself, Lightspeed Masayuki?!