Instructions:
(100% extra pet damage for 15 seconds)
1) Take your hunter, mage or warlock pet to Shadowmoon Valley. Find the mob "mutated horror" in the fetid pool.
2) Get 10 stacks of its debuff "mutated blood" on your pet, dismiss it.
3) Summon pet in instance
(15% extra pet damage for one minute)
1) Do above for mobs in the tainted forest in blasted lands, with their feltaint debuff
So far as I know this can be taken anywhere and stays on your pet.
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