Pounce damage is affected by attack power. Empirical data gathered by player Staralfur in patch 2.0 suggests this calculation:
Base Damage + .18 x Attack Power
This ability can be considered as the equivalent of the Rogue ability Cheap Shot. Cheap Shot has a 4 second stun duration, while Pounce has a 3 second stun duration, but this can be increased to 4 with the Brutal Impact talent. Unlike Cheap Shot, Pounce has an additional bleed effect, and Pounce costs only 50 energy compared to the 60 energy cost of Cheap Shot. Also, Pounce awards only one combo point while Cheap Shot awards two.
A helpful initial attack when you need to get in a couple of attacks before the target has a chance to do anything.
Also helpful when sneak attacking an enemy with a group.
However, if you wish to deal the most damage possible in a shorter duration and/or if stun or bleeding effects aren't useful on your target (immunity, for example), you may use Ravage (Druid) as an opener. Some things that are immune to bleeds can still be affected by the stun, which may allow you to get off one or more Shreds.
Patch 3.1.0 (2009-04-14): No longer affected by diminishing returns with other stuns, however, it now shares a diminishing return with Cheap Shot (Rogue).
Since 2.0.1, Pounce Rank 4 lasts 3 seconds and deals 600 damage, increased by attack power, doesn't require behind target. It is now a reliable opener for Cat Form.
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