My favorite:
At 80 I personally love farming the converted heros in the valley of fallen heros in Icecrown (http://www.wowhead.com/?npc=32255). The multi-mob pulls give pets half a bar of xp at level 75 and around a third of a bar at 79. After putting down an explosive trap at my feet I pull with a volley and wait until they set off the trap before doing another volley right ontop of my pet and myself. I only need to do a volley once or twice before the mobs drop and my pet gains that lovely half a bar. As for the hunters, you gain a nice chunk of gold from silver (the mobs drop around 20-40 silver on average for each) and vendor trash. I would recommend farming these as marksman with Imp. Barrage (http://www.wowhead.com/?spell=35111) and in blue gear at least. I have seen the pulls farmed in other specs though. You will just drain more mana from having to keep casting volley when it gets interrupted. The mob groups have a quick respawn timer so by the time you kill off ten or eleven groups, the first group you killed will be back. The time seems to pass a whole lot quicker gaining the xp in-mass like this so the location and mobs have become a fast favorite of mine.
Recommended itmes:
Engineering bombs for groups that don't die after just one volley
Runic healing pots for pulls gone wrong
Runic mana pots for when you forget to regen mana between pulls (<- has done this before)
Heavy frostweave bandages to heal between pulls
Plenty of food and water for when health and mana become a must
An epic flyer to get from one group of mobs to another quicker
I would also get a good playlist or music station to listen to while grinding out the xp. I personally listen to the stations on http://www.sky.fm/ =)
So how about the rest of you? Any good pet xp grinding locations/tips?
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