Taunt is a core warrior ability learned at level 12. It is a single target debuff which forces the mob to attack the warrior for three seconds, generating enough threat so the warrior matches the current top entry in the mob's aggro list. Taunt is instant-cast, does not trigger the global cooldown, costs no rage and has an eight second cooldown.
Some mobs (most bosses in particular) are immune to taunt. Non-immune mobs must be hit by Taunt using standard hit mechanics. Taunt has no effect on enemy players in PvP and does not have any effect when the warrior already has aggro on the mob (except the mob is still forced to target the warrior for three seconds).
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Taunt is one of the signature moves of a tanking warrior. It may help aggro buildup greatly, and it may be a life-save in certain situations. On the other side it has a rather long cooldown, so it must be used with care with a good grasp of the overall situation (multi-mob pulls in particular). It should also be understood that after three seconds, the mob may immediately turn to another target if the tank's aggro buildup was lower than that of the other player(s).
A melee damage dealer has 1000 points of threat on a mob. A warrior taunts the mob, thereby immediately gaining a threat value of 1000, and forcing the mob to attack the warrior for three seconds. After that time, threat works normally for the mob, and if no one is at 130%/110% (ranged/melee) of the tank's threat, the warrior remains the mob's target.
Normally, hunters can help a tank's initial aggro buildup with Misdirection. If that's on cooldown, it's possible to use a combination of Taunt and Feign Death to achieve the same effect. The hunter pulls, using his most aggro intensive abilities. When the mob is about to hit the hunter, the warrior Taunts and the hunter Feigns Death. Misdirection is the safer method though, as both the Taunt and Feign Death can be resisted by the mob.
- Miss chance
Based off testing post Patch 4.0.1 on Growl and Dark Command, taunt no longer has a miss chance for a level 80 vs a boss. Prior to this, Taunt is treated as a spell. It couldn't be cast when silenced and it had a 17% chance to miss raid bosses (in contrast to the 8% chance to miss boss mobs for melee attacks). So even if you were melee hit capped (263 hit rating at level 80), Taunt's chance to miss was still 9%. This 9% gap could be mostly covered with Glyph of Taunt (removed in Patch 4.0.1.
- WotLK/Cataclysm Patch 4.0.1 (patch date::12-Oct-2010): Removed miss chance of this effect. (Untested, based off testing on Growl and Dark Command)
- WotLK Patch 3.0.8 (patch date::2009-01-20): Range increased to 30 yards, from 20 yards.
- TBC/WotLK Patch 3.0.2 (patch date::14-Oct-2008): Range increased to 20 yards, from 5 yards. Cooldown reduced to 8 sec.
- TBC Patch 2.3.0 (patch date::13-Nov-2007): The chance for this ability to land successfully on its target is now increased by hit rating. However, Taunt remained classified as a spell for the purposes of determining miss rate versus mobs. That means that against a mob 3 levels higher than the player, Taunt has a base chance of 17% to be resisted (a miss).
- Vanilla WoW: on release, Taunt did not create extra aggro for the warrior, it only forced the mob to attack the warrior for 3 seconds.