Chromaggus. For some of us the name will induce terror filled nightmares of endless wipes, for others it will be the hours of grinding for transmog gear.
But, one change that came when Cataclysm was launched was that it was now a tamable hunter pet!
Chromaggus was the 2nd to last boss of Blackwing Lair (BWL). He was perhaps more challenging than the end boss, Nefarian, due to the debuffs he can cast on players.
As a hunter pet he is beautiful. Although there is a rare spawn pet that now shares his skin, the best way to tame this beast is to simply head into the dungeon.
Chromaggus is also a challenge tame for two reasons: first, being the second to last boss in a raid, you must be in a raid group (all members must be level 60 or higher) and second, you cannot get past the first boss without at least one more player to help you out. Although every other boss in the raid is easily soloed be a level 80 hunter with a good tenacity pet, the first boss is quite a challenge, making this pet rather hard to come by.