Crystal Prison

A dungeon made entirely of crystal — floors, walls, traps, monsters, and the thing imprisoned at its heart. The crystal magnifies magic unpredictably and allows you to see through walls to the monsters on the other side, and them to see you. The prisoner at the center is a creature of pure light sealed inside because it drives anyone who looks at it permanently, irreversibly sane — unable to hold any belief that isn't provably true.

Play this campaign right now with an AI Dungeon Master that narrates the world, voices every NPC, remembers your whole story, and asks for the rolls — solo or with friends.