WoWDB

Holy Shock leaves a Glimmer of Light on the target for 30 sec. When you Holy Shock, all targets with Glimmer of Light are damaged for [ 192% of Spell Power ] or healed for [ 228% of Spell Power ]. Glimmer of Light's total healing and damage is increased by 6% for each target affected, but is split evenly between each target.

You may have Glimmer of Light on up to 3 targets.