Lots of people kept making whos the toughest boss threads, but who's the toughest lackey? Strictly only on the content patch they were released(aka no 5.3 upgrades/cloaks on ToT for example) and no zone debuffs.
Probably not gonna list m'uru since he's the toughest in sunwell anyway. Plus everyone just parrots what level 1 guy on the blizz forum says and he'd win by a mile, even though he'd probably be tougher than anyone here anyway.