Dungeon ni Deai wo Motomeru no wa Machigatteiru Darou ka EP12 (Show) Evil Intentions

A massive floor boss has crashed down from the upper floors and begun tearing apart the adventurers. Aiz has left for the surface, and it's up to Bell and his friends to defeat the monster. With their escape route cut off, it's do or die if they ever want to see the light of the sun again.