Unless the Cataclysm itself wipes them out, they'll still be neutral. The goblin cartel that runs places like Gadgetzan and Booty Bay is not the same cartel that is joining the Horde. They're two different groups.
"Who would win in a fight? The Lich King or Deathwing? No fanboy comments, I'm talking about their powers and abilities in lore."
Assuming the fight is done in the style of our Two Bosses Enter series (which is way fun, you should read it if you don't), where the fight is one on one in territory that doesn't give either of them a significant advantage outside of fun flavor... I'm with Deathwing. He'll just spew lava at the Lich King from the sky or make the ground split open and eat him. The Lich King is a pretty damn scary death knight, but against the dragon that holds dominion over the earth itself, he's pretty much screwed unless he gets lucky and the moon randomly falls out of the sky to squish Deathwing.
Even in a situation where you give the Lich King his Scourge, most of them are completely useless when you consider the fact that Deathwing is a dragon and can fly whenever he pleases. The only members of the Scourge that would still matter are gargoyles and the val'kyr. The Lich King's endless supply of shock troops are suddenly worthless to him.
"I have a question. Will there ever be a only healing class or only tanking class? I would do it to avoid the hybrid tax."
The "hybrid tax" doesn't exist for healers or tanks, only DPS. Especially when you consider every single tank or healer as at least a 2-role hybrid. Any hybrid tax that could potentially exist is nullified because every single tank and healer would be taxed the same way. It would be pointless to even plan one out. There is no tax for them.
I think it's unlikely that we'll see a healing only or tanking only class at any point in WoW's lifetime. Giving those classes DPS specs allows more of them to enter the endgame, not to mention a pure heals or pure tanking class would have a horrible time leveling up or soloing. WoW has always tried very hard to make sure every single class can solo effectively, without it being a huge pain.
el ranchero asked...
"Has Blizzard given any indication whether or not they consider the 'platform method' of gimping the Lich King encounter in HoR an exploit? If not, do you have any idea if they plan to?"
They never banned anybody for it, as far as I know. It's pretty clear they didn't like it and it wasn't intended, though. As of patch 3.3.2, the Lich King will kill you instantly if you try to use that strategy. As a rule of thumb, if a boss up and murders you, it means you're doing something wrong. Using the platform method is most definitely doing it wrong.
Besides, even if Blizzard didn't end up fixing it, it's super cheesy and you're doing yourself a disservice by using it. It really sucks the fun out of that instance. I always hated when my PUGs made us do it. Let me tell ya, nothing's more fun than tank, healer and one DPS running up to do it normally while two dippy casters go take naps on the ledge without saying anything because they assumed the entire group likes cheating. Thanks for wiping us, guys. Appreciate it!
Next on my list of things I want them to fix is the ability to ride mounted past the groups of caster mobs after Ick and Krick in Pit of Saron. That, too, is super cheesy.
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