Orb of Chaotic Assault

Orb of Chaotic Assault is a magic item (wondrous item) of rare rarity.

This iridescent glass sphere’s color is constantly shifting. When used as an improvised weapon the orb breaks on impact. If the orb shatters against a creature, one randomly determined resistance or immunity the creature has is reduced for 1d6+1 rounds, after which the creature’s defenses return to normal. A creature’s immunity to a damage type changes to resistance to that damage type, or it loses its resistance. Success on a DC 15 Intelligence (Arcana) check reveals what resistance has been affected after the orb is used.