Orbit-uary (10 player)

Kill the Flame Leviathan on the hardest hard-mode on normal difficulty.

There are 4 defence towers in the gauntlet leading to the Flame Leviathan which can be activated by talking to the Lore Keeper of Norgannon before talking to Brann to start the gauntlet. Activating a tower and leaving it intact will activate a unique Orbital Defense System on the Leviathan. Each Defense System grants the Leviathan an extra ability, increases his health by 40% (multiplicative!), gives him a unique buff, converts all dropped Emblems of Valor to Emblems of Conquest and increases the number of Emblems. Killing the Leviathan with all Defence Systems active is the hardest hard mode and allows the raid to get the Orbit-uary achievement, 3 Emblems of Conquest and 1 piece of loot from the Hard-Mode loot table, in addition to the normal loot.

The following abilities complicate the fight when all 4 Defense Systems are active:

• The Flame Leviathan has 88 million HP
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• Tower of Storms: Thorim's Hammer - Physical damage. Extra damage at point of impact. Also increases physical damage by 25%
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• Tower of Flames: Mimiron's Inferno - Fire damage and a AoE damage zone. Also increases fire damage by 50%
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• Tower of Frost: Hodir's Fury - Frost damage and entombs vehicles near the impact point in ice. Entombed vehicles are stunned for 1 minute, taking damage over time. The tomb can be destroyed with fire damage, a single cannon shot will suffice. Also slows players for 20%
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• Tower of Nature: Freya's Ward - Nature damage and summons Writhing Lasher and Ward of Life adds. Also decreases fire damage taken by Leviathan by 10%

HP and loot results of leaving up fewer towers with Hard Mode active:
0 Towers | 1 Towers | 2 Towers | 3 Towers | 4 Towers
HP [mln] 23 | 32 | 45 | 63 | 88
Emblems 1 | 2* | 2* | 3* | 3* (* = Emblem of Conquest)
Loot normal | normal | normal | normal | Normal + hard

Be level 100+.
Enter Ulduar.
Go down the stairs.
Talk to Lorekeeper Norgannon.
Tell him to activate secondary defenses.
Mount up.
Ride directly to the gate at the very far end of the very long room.
Kill everything in sight.
See gate get smashed as Flame Leviathan comes to kill you.
Kill Flame Leviathan instead.
Get achievement.
Dance like Snoopy.
Carry on.

Two-manned this last night with a level 90 Blood Death Knight and Mistweaver Monk wearing greens and blues from MoP questing -- approximately 435 itemlevel. (Not that our classes mattered for this fight, as it is entirely vehicle-based.)

Neither of us had ever been to Ulduar before this achievement run, and went into each fight with only a few minutes of research into the hardmode achievement beforehand.

This fight is one of the more difficult ones to get used to due to the unfamiliar vehicle mechanics, but easy once you get the execution down.

Clearing the trash:

Talk to the Lore Keeper of Norgannon at the entrance and tell him to start up the defense systems. This will activate the four towers that cause the achievement. Then talk to Brann and start the encounter.

Have each person get into a Salvaged Demolisher and head out. Destroy the towers that the iron dwarf mobs are coming out of, because they will keep spawning until the towers are destroyed. These are NOT the towers that trigger the achievement, so don't worry about that. If you aggro helicopters, move away from them so they come closer to the ground, then kill them with boulders.

Do not kill the last of the mobs at the closed northern gate until you are ready to fight the boss, because this will cause the fight to begin.

If you wipe on the boss, all of the vehicles will be moved to the boss area, and the teleporter at the entrance will take you directly back to that spot so that you can quickly start again.

Boss Strategy:

No matter how epic you think you are at level 90, you MUST fight in vehicles. With all four towers up, he has 88 million health, far far more than any other boss you will fight in this tier. Even at level 90, he will very rapidly murder you if he catches you outside of a vehicle.

Each player will drive their own Demolisher. For this fight, you have two buttons that matter. Both of these abilities can only fire straight ahead, and the vehicles cannot strafe.

Hurl Boulder (on 1) deals some damage to the targeted area with no cooldown or resource cost.

Hurl Pyrite Barrel (on 2) causes a stacking DoT debuff to the targeted area and costs 5 units of fuel. You start with 50 units, and don't really have any way of getting more fuel once you run out (that I could figure out) so you basically have ten uses of this ability before it runs out.

The key to this fight is to refresh the DoT late so that it ticks as much as possible, but DO NOT LET IT FALL, because you're depending on those higher-stack ticks to do most of the damage. A rotation of 2-1-1-1 worked pretty well for me, though you can probably wait longer before refreshing it if you're confident in your latency.

Ignore the plants and lights and all that other stuff going on around you. Your vehicles have several million health at this item level, and you should outlast all of that stuff. Trying to dodge all of it will just mess up your rotation.

Start the fight from opposite corners of the room. Flame Leviathan will choose one of you as a target and start moving slowly towards you. That player will need to move backwards towards a corner while the other player follows at a safe distance. Both players are following their rotation the whole time. Before he reaches the first target, he should switch targets to the other person. The second player should then start moving backwards.

Both players' DoT stacks should reach 10 and the boss will die shortly after. If you failed to keep the stacks up the whole time, or stacked them up to 10 too quickly, he will likely still have between 5 and 15 million health left, and there is no way you're going to take him down the rest of the way with nothing but boulders. The boss and all of his adds will quickly overwhelm you. We wiped three times before we got it down just right.