Sooo he will be nerfed to only drop one mana bomb.
But seriously.
I think the fight will be a mix of a few of the lesser characters. Magatha will probably come back either trying to join garrosh for a power grab on thunder bluff of just to kill baine in the dungeon. I'm pretty sure garrosh will probably have some blood elf with him. Of course the second to last boss will probably be malkorok in a super buffed sha mode.