Devouring Plague

Devouring Plague is a Shadow priest ability. It is an instant cast Shadow-based spell that consumes 50 Insanity to deal instant damage and apply a strong damage over time debuff, healing the caster each time it deals damage.

• Ticks scale with haste and damage dealt can critically strike (healing returned cannot crit).
• Devouring Plague is the only baseline ability that costs insanity.
• Shadow priests may talent into Searing Nightmare which also costs insanity and competes with Devouring Plague in multi-target scenarios.
• Uses the same refresh mechanic as Mastery: Ignite, where reapplying the effect early will roll all of the previous remaining damage into the newly applied DoT. This means that unlike other DoTs, refreshing Devouring Plague early at any point will never cause a loss of damage.

• Devouring Plague is one of the three periodic effects that "applies" Mastery: Shadow Weaving to the target. Therefore it is ideal to refresh the effect near its end in order to maximize its uptime, so long as the priest will not cap their insanity doing so.
• While in Voidform, shadow weaving applies its full effect to all targets regardless and players should instead prioritize casting Devouring Plague whenever possible.
• As a disease, Devouring Plague can be dispelled by abilities such as Detox and Purify Disease. Devouring Plague has no dispel protection on its own, but it can benefit from the dispel protection provided by Vampiric Touch and Unstable Affliction against dispel abilities that remove both disease and magic effects (such as Cleanse).

• For a time between patch 9.0.1 and patch 9.0.2, Devouring Plague was learned before Shadowform. Since Shadowform is necessary to use Devouring Plague, this made the skill unusable until Shadowform could be learned. Eventually, the levels at which Shadowform and Devouring Plague were learned at were swapped.

• Devouring Plague (Scourgewar), TCG card