Spell mirror

Spell mirror was a wizard spell from the school of alteration.

Effects
This spell was cast on a reflective object such as a mirror. The mirror was then placed in a strategic location as a trap. Any medium-powered spell, or discharge from a magic item, cast at the mirror would harmlessly enter the mirror and charge it. The mirror held the charged spell until it was either broken or looked at by targets specified by the caster, at which point the stored spell was released at the targets.

Components
In addition to verbal and somatic components, this spell required as material components a mirror and a handful of dust from an object that was once enchanted to cast. The mirror was damaged during the casting.