Catalyst Oil

Wondrous item, rare

This special elemental compound draws on nearby energy sources. Catalyst oils are tailored to one specific damage type (not including bludgeoning, piercing, or slashing damage) and work once per dose. Whenever a spell or effect of this type goes off within 60 feet of a dose of catalyst oil, the oil catalyzes and becomes the spell’s new point of origin. If the spell affects a single target, its original point of origin becomes the new target. If the spell’s area is directional (such as a cone or a cube) you determine the spell’s new direction.

This redirected spell is easier to evade; if it allows for a saving throw or attack roll, its saving throws are made with advantage and the attack roll is made with disadvantage (using the caster’s spell attack bonus).