Tanks in Dragon Soul

[Argg0]

I was checking on the Dungeon Journal logs and couldn't really define how many tanks will be necessary for each boss. Also, there is no mention of tank swap being required in Ragnaros, but we all know it is, so DJ lacks sometimes in info.

Anyone could help me with that? I'm mostly interested in 10m

From what I've gathered:
Morchok has Crush Armour. Reducing armor and probably requiring a tank swap. Though, in heroic... One tank would both? Then other would take them?
Zon'ozz has Focused Anger? Increasing his damage against the primary target, right? So, swap tanks?
Yor'sahj has Void Bolt, reducing the healing done.
Hagara has adds, are they tanked? Do they require two tanks? She also has that Ice tomb, would that be cast on tank?
Ultraxion's entree in the journal copies I've found is incomplete, but from what I've seen he has a threat drop ability that should require swap, right?
Warmaster Blackhorn same as Ultraxion, couldn't find much info, but it has lots of adds, right?
Spine of Deathwing seems to have a lot of adds.
Madness of Deathwing seem to have a lot of adds.

So, all fights require two tanks? Is that correct?

[Deleted]

Morchok requires two tanks for tank swap, heroic is possible with one if you use some cooldowns.

Yor'sahj the unsleeping can be done with one tank even if the debuff stacks, we did it and seen plenty of others done it.

Warlord Zon'ozz only need one tank, focused anger increases the damage dealt by the boss so it doesnt matter who hes hitting, and no adds so no tank swap needed.

Hagara the Stormbinder only need one tank aswell, shes not attacking you while the adds spawns so only need one tank here aswell, same on heroic mode.

Ultraxion requires two tanks because of the fading light debuff, if a tank gets targeted with it everyone in the raid will wipe since he has to leave the twilight realm and cant generate any threat.

Warmaster Blackhorn requires two tanks since you get two adds on each side which puts different debuffs on the tanks, they need to swap adds and also swap on the boss later on.

Spine of Deathwing can be done with only one tank if your group is smart enough, if you wanna play the safety side you can use two.

Madness of Deathwing, it was a "showbreaker" when we tried it on PTR and we only used one tank there, might been changed since then I actually dont know anything about that fight in general now.


So to answer your question, two fights are 1 tank fights, while the Deathwing fights can be done with only one unless they have changed it.
Edit: Yor'sahj is also optional