Glimpse of the Void
8th-level · Enchantment
Casting Time 1 action
Range 120 feet
Components V, S, M (a scrap of parchment with Void glyph scrawlings)
Duration Up to 1 minute (concentration)
Muttering Void Speech, you force images of terror and nonexistence upon your foes. Each creature in a 30-foot cube centered on a point within range must make an Intelligence saving throw. On a failed save, the creature goes insane for the duration. While insane, a creature takes no actions other than to shriek, wail, gibber, and babble unintelligibly. The GM controls the creature’s movement, which is erratic.
Source: Deep Magic 5e · OGL/Open