Priest · Shadow Magic · tier 1 · from level 10

Blackout

Rank 5/5

Gives your Shadow damage spells a 10% chance to stun the target for 3 sec.

Doesn't change the damage or healing of any Priest spell.

Averages, counting crits and misses, for a level 60 Priest with a typical weapon and no other gear or buffs, against a target your level. Worked out from the game's own data, the same way as the Foresight addon.