Priest · Shadow Magic · tier 7 · from level 40 · needs Vampiric Embrace

Shadowform

+97.3 Devouring Plague

1/1 · level 60 · per cast · and 4 more

Shadowform

Rank 1/1

Assume Shadowform, increasing your Shadow damage by 10%, reducing the Mana cost of all Shadow spells by 50%, increasing the critical strike damage bonus of your Shadow spells by 100%, and reducing Physical damage taken by you by 15%. However, you may not cast healing spells while in this form.

Devouring Plague +11.8% +97.3 Shadow Word: Pain +11.8% +87.4 Mind Blast +11.8% +56.2 Mind Flay +11.8% +44.7 Shadow Word: Death +10.0% +44.7

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.