Engaging with this encounter will remind you a lot of the airship battle from way back in Icecrown Citadel. Similar to that fight, one of the big things that you need to watch out for is that the ship that you’re on, the Skyfire, has it’s own HP bar and if it dies, so will you. So you’ll have to take as much care of the ship as you would your main tank.
You can’t heal the ship so your only real method of taking care of the damned thing is prevention. There are three main thigns that will hit the ship during the fight. Blackhorn’s mount will cast a spell called Twilight Onslaught at the ship which you can see as a swirly purply thing heading towards the ship, marked by a swirly purple mark. If the purple ball is allowed to connect, it’ll do a huge amount of damage to the ship so you and your raid need to intercept it it by standing IN the thing on the ground. The damage is split amongst whoever’s standing in there so get as many people into the mark as you can to make the damage more managable.
There’s a much smaller version of this cast by the drakes which is managed the same way but deals much less damage so it doesn’t take as many peple to soak.
The third method are the sappers who will drop onto the deck of the ship and run for the cabin where they turn into suicide bombers and deal a HUGE amount of damage to the ship so they need to be cc’d and killed asap.
Throughout this there are two types of adds, Dreadblades and Slayers running around that need to be picked up and held close enough together that they can be cleaved but not close enough that both tanks are getting the stacking debuff from each add so it’ll take a bit of management at first but a few tries and you and your offtank should get sense of distance needed.
There will be three waves of these pair of adds so to negate their stacking debuff, the tanks will need to alternate which one they tank from one wave to another to give the debuff a chance to drop off.
After three waves of this, Blackhorn will land and phase 2 will begin.
His dragon will stay overhead hurling void zones on the ground that need to be moved OUT of instead of gathered under so watch out for that and deal with Blackhorn.
He’ll stack an armor debuff on the tank he’s on so there’s a tank swapping going on that’s nothing really new. Figure out what amount of stacks your raid is comfortable dealing with and switch out from there.
He throws out an aoe that will hit everyone that can’t be avoided and one that can where he targets someone randomly and throws out a conal aoe so if you see him getting ready to unlease that, you need to step lightly and get the hell out of the way.
He will also increase the damage he deals as he gets lower in health so keep a ready finger on your cooldowns as the fight nears completion and you should be fine.
This is the last fight before you take on Deathwing so when you manage to get him down, better put on the big boy pants because this ride is almost done.