Patch 10.0.2 (2022-11-15): Can now only be cast on players.
Patch 10.0.0 (2022-10-25): Now a row 5 class talent (was a level 58 ability).
Patch 9.0.2 (2020-11-17): Re-added and redesigned as a level 58 ability for all priests (was a level 100 Discipline and level 90 Shadow talent). Infuses the target with power for 20 seconds, increase Haste by 25%. 2 minute cooldown.
Old: Infuses you with power for 20 sec, increasing haste by 25% and reducing the mana cost of all spells by 25% (Discipline) or increasing Insanity generation by 25% (Shadow).
Power Infusion has been moved to level 100 for Discipline (was 75).
Power Infusion reduces mana costs by 25% (was 20%).
Patch 7.0.3 (2016-07-19): No longer available to Holy priests, and now available at level 90 for Shadow priests (was 75). Now increases Insanity generation for Shadow priests.
Patch 6.0.2 (2014-10-14): Now grants 25% Haste (up from 20%), but no longer increases damage (down from 5%).
Patch 5.2.0 (2013-03-05): Now increases the Priest's damage by 5% in addition to current effects.
Patch 5.0.4 (2012-08-28): Now a level 75 talent (was a tier 3 Discipline talent). Mana cost removed and duration increased from 15 sec to 20 sec, but can now only be cast on the priest.
Patch 4.0.1 (2010-10-12): Moved to tier 3 (was tier 7).
Patch 3.1.0 (2009-04-14): This effect now has a new spell effect and sound.
Patch 3.0.2 (2008-10-14): Cooldown reduced to 2 minutes, down from 3.
Patch 2.4.2 (2008-05-13): Will now consume the correct amount of mana when cast on yourself.
Patch 2.4.0 (2008-03-25): Redesigned. Infuses the target with power, increasing their spell haste by 20% and reducing the mana cost of all spells by 20%. Lasts for 15 seconds. This will not stack with other haste effects, such as Heroism or Bloodlust.
Old: Infuses the target with power, increasing their spell damage and healing by 20%. Lasts 15 sec.
Patch 2.1.0 (2007-05-22): This ability is now unusable on Rogues or Warriors.
Patch 1.10.2 (2006-05-03): This ability will no longer stack with [Arcane Power]. If you gain both at the same time, Arcane Power will take precedence.