Press Q to look at the pile of corpses. Press SPACE to laugh. If you look at the corpses, you will lose sanity. If you stand around the shadow creature, you will lose more sanity. If you laugh, you will restore sanity. If you touch the shadow creature, you will take damage, if your sanity is low enough.
This is a test of a sanity system. I might create a platformer that uses sanity as a mechanic.