It can only cancel an aura that exists, you can't cancel a buff you don't have.
Originally Posted by Brox703
The best example Martie already covered.
Those two aura are often used to clense physical debuffs. One prime example would be the impale debuff of Gormok in Trial of the Crusader. Another example would be to make a macro to cancel all health benefiting buffs during the third phase of Anub'arak. Something to the effect of:
/cancelaura Divine Shield
/cancelaura Hand of Protection
Cancelaura is often useful in very specific situations, however it isn't something you would use all the time because you are in fact canceling buffs. 99.99999% of the time, you like buffs.
/cancelaura Prayer of Fortitude
/cancelaura Greater Blessing of Kings
/cancelaura Gift of the Wild
/cancelaura Commanding Shout
One example of how in the past buffs could be actually bad is how Balance druid DPS functioned prior to patch 3.2. Prior to that patch, both of the Eclipse buffs were on a 15 second duration, 30 second cooldown and couldn't be active at the same time. Because one was calculated to be more benefitial, in order to do the best DPS, a Balance druid would actually cancel the weaker buff early when the other buff was off its cooldown so that it could be procced sooner, thus increaseing DPS. 3.2 fixed this issue by making it so that whenever the buff procs, the other cooldown is reset to 15 seconds, so that even if the buff is canceled early the other could not proc until the duration of the buff has past anyway. It is no longer benefitial for them to cancel the buff early.
Last edited by Quinafoi; 04-06-2010 at 11:04 PM.
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