Psychotic Undertow

Feats

This island is affected by a magical undertow flowing beneath it. Whenever a creature with at least 3 levels in an arcane or divine spellcasting class casts a spell, it must make a Will save (the save DC is based on the island's challenge rating). On a failed save, the creature becomes confused and goes into a rage similar to a barbarian's rage for 1 minute. After the effect ends, the creature gains a +1 bonus on Will saves for 1 minute.