Devilsaurs appear to be the first of the exotic pet families, although at the moment they can be tamed by any hunter.
Ferocity talent tree
http://petopia.brashendeavors.net/ht.../wotlkpets.php
Monstrous Bite
Your devilsaur ferociously bites the enemy, causing damage, and boosts its own attack power by 5% for 12 seconds. This effect stacks 3 times.
25 Focus, Instant, Melee Range, 10 sec cooldown
WOOt BM hunter FTW