Rapture

Rapture is a Tier 4 Discipline priest talent that restores 2/5/7% of the priest's total mana upon their Power Word: Shield being dispelled or completely absorbed.

Previous Bug

 * Up to and at least through Patch 3.0.8 this ability appears to return mana based on the priest's target and not the priest making this ability mostly useless (except mildly helpful when heal/shield a paladin or feral druid).