- "How do you know which one is real?!"
Mirror Image is a Mage spell of the Arcane tree. Casting it creates three copies of the Mage around him that cast spells at his current target and have a fraction of his health and spell power. This ability was added in Wrath of the Lich King and is trainable at level 50.
This spell was previously not affected by the global cooldown nor triggered it. However, since Patch 3.1.0 this spell is on the global cooldown, making its activation a slight DPS loss. However, it does not trigger a GCD on every other Mage spell that doesn't have a global cooldown such as Cold Snap, Icy Veins, Combustion and damage trinkets.
The images created do low damage and receive a percentage of the Mage's spell power. They cast 3.0 second Frostbolts and occasionally shoot Fireblasts. Mirror Images inherit the spell hit rating on their master's gear (but not that of talents like Elemental Precision).
Mirror Images inherit 33.33% of their master's spell power each. their Frostbolts do 163-169 + 30% of that spell power as frost damage and crit for 150% of their normal damage (aside from snaring their target by 40% for 4 secs), while the Fireblasts do 88-98 + 15% of that spell power as fire damage and crit for 150%.
Tips and tactics
The Mirror Images inherit the Mage's threat lists, and the Mage also gains a 90M threat reduction debuff like Fade. This makes it useful as a last-ditch threat dump. The images do an average of 15k damage over 30 seconds with no spell power, which is highly useful for single-target DPS in raids and sustained PvP burst.
At recent moment (Patch 3.2.2a) there are multiple reports that Mirror Images still sometime break crowd control even with instant spells (Fire Blast), whereas Patch 3.1.2 notes say that Images "should no longer cast Fire Blast or Frostbolt on targets that are affected by crowd control debuffs that break immediately on damage unless they are already casting these spells when crowd control is applied.". Considering that Fire Blast has no cast time, Mirror Image must acquire already crowd controlled target to cast it and break control.
Proof from recent worldoflogs.com report (translated): [23:35:49.605] Mirror Image's Fire Blast breaks Maz'dinah's Polymorph
- Patch 3.3.0 (08-Dec-2009): Health on the mirror images has been increased.
- Patch 3.2.0 (04-Aug-2009):
- Images will no longer trigger the death sound when their time expires.
- The mirror images will no longer complete casts of Frostbolt on targets which are Polymorphed at the time their Frostbolt channel finishes.
- Patch 3.1.2 (2009-05-19): The images summoned by this spell will now target the creature that most hates the Mage, and should no longer cast Fire Blast or Frostbolt on targets that are affected by crowd control debuffs that break immediately on damage unless they are already casting these spells when crowd control is applied.
- Patch 3.1.0 (14-Apr-2009): Mirror Image will no longer cast Polymorph.
- Patch 3.1.0 (14-Apr-2009): Mirror Image now triggers a global cooldown on all spells.