Prismatic Rune

A magical rune is etched on this small stone made of multicolored quartz. When you finish a Long Rest, choose one of the following damage types: Acid, Cold, Fire, Lightning, or Thunder. The rune is imbued with the chosen damage type until you finish another Long Rest.

Charges: The rune has 6 charges and regains 1d6 expended charges daily at dawn. When you cast a spell that deals damage, you can expend 1 charge to change the spell's damage type to the damage type chosen for the rune.