Mimiron

Mimiron is one of the more complicated fights in Ulduar. In comparison with the other 3 keeper bosses (Hodir, Thorim, Freya), this boss is extremely difficult.

You battle four of Mimiron's vehicle creations: The Leviathan MK II, which is his personal version of the Flame Leviathan; VX-001, which is a robotic unit; the Aerial Command Unit, which is a flying vehicle; and the ultimate V0-L7R-0N, which is a combination of the previous three.

The challenge of this fight is avoiding the many ways you can die if you are not completely focused.

Phase 1

Mimiron will use his Leviathan MK II to swap between melee and ranged attacks.

Ranged DPS and healers spread out, and not move for the rest of the phase. The boss will shoot a fire ball at one person that will put a DOT on them and they have to be healed through it.

The boss does an ability called Plasma Blast that hits the main tank for 17,600 damage per second unmitigated for 5 seconds. The tank must be spam healed through this. A cooldown rotation is highly recommended for both the tank's cooldowns and any other mitigation cooldowns in the raid, such as Guardian Spirit.

After each plasma blast, the boss will do a shock blast. You can see him casting this ability (blue lightning arcs), and melee and the tank have to run away from him. The ability is a self-centred AOE that will one-shot anyone in range. If the run distance back to the boss and timing are executed perfectly, a tank can keep the boss from moving when they go back in.

Proximity Mines will be a danger to the melee if they don't watch out where they run. Although one mine is not life-threatening, two or more can kill you. Having no one in the raid step on any of the mines throughout the entire fight is an achievement of its own.

Phase 2

At the beginning of phase two, stay away from leftover mines; they will explode by the start of the phase. Spread out around the room, then group up behind the boss when he enters through the central platform (even healers and ranged).

VX-001 is the next vehicle. It's a robotic unit that has no aggro table and shoots Rapid Bursts at random people. Melee DPS should continually run behind the boss each time he turns.

Heat Waves will cause a lot of raid fire damage. The occasional Rocket Strikes will mark a small circle on the ground and fly to it, killing anyone standing over.

Whenever Mimiron begins to cast Winding Up, everybody should stack behind him and move slowly as he rotates, in order to stay behind and avoid the ability called Laser Barrage. Casters and Ranged DPS should stay close to Mimiron to make the avoiding of the laser easier. Anyone caught in front of the boss during this ability will be killed instantly. This ability only goes 180 degrees and only goes in one direction, so just run behind him. Melee should be careful not to stand too far into the boss's center or the barrage may clip them.

Phase 3

An Aerial Command Unit is the third vehicle. It will be attackable only by Ranged DPS. A ranged tank, such as a warlock, will be keeping the boss stationary.

On this phase the tank should be picking up assault bots (which spawn from orange beams of light) and junk bots (which spawn from green beams of light). Assault bots will one-shot a non-tank so it is crucial that they are picked up; junk bots do not hit hard so if one is loose it is not a priority until assault bots are secured. All melee DPS should be on these bots while the command unit is in the air. Assault bots can be stunned, and will also do a channelled spell 'magnetic pull' that stuns the tank. This is interruptable.

Assault bots drop an item called magnetic core. One person will pick these up and put them below the boss. This will pull the boss onto the ground; everybody should DPS him during this time.

All ranged should have a macro '/target Bomb Bot'. Bomb bots will spawn throughout this phase; they run very fast and will likely kill anyone they get to. Ranged must target them as soon as the bots drop through the air. They should be dead within a few seconds of hitting the ground so that they don't get near anybody; if a bomb bot is coming toward you, run away.

Phase 4

After the command unit is down, kill any remaining bots and get into the same positions as in phase 1.

After the Aerial Command Unit is defeated, Mimiron will create his ultimate vehicle - V0-L7R-0N, a combination of all three vehicles he has used so far. Each unit starts at 50% health. Melee are only capable of attacking the bottom and middle. All of these parts must be killed within 5 seconds of each other or they will self-repair.

The different parts keep some of their abilities. MK II keeps Shock Blast and Proximity Mines. VX-001 keeps P3Wx2 Laser Barrage and Rocket Strike, while gaining a more powerful version of his Rapid Burst, called Hand Pulse - a single pulse that damages players between the caster and a random target. Aerial Command Unit will keep Plasma Balls.

Tanking is very sensitive during this phase. It is important to move the boss as little as possible, and to reposition quickly after shock blast. Note that the boss can do shock blast and laser barrage right after each other; this is difficult to handle. During the laser barrage the bottom of the boss can be turned seperately from the middle so that the tank can avoid being hit.

Hard Mode

Mimiron's Hard Mode is activated by pressing the gigantic "DO NOT PUSH" button in the back his room, which triggers an 8-minute self-destruction timer on his chambers.

You will have 8 minutes to kill all 4 Vehicles in order to succeed. Emergency Mode increases Mimiron's health and damage by 30%. He will also set his chambers on fire, and will use a different mechanic during each phase to deal with it:

Fiery Explosions - Mimiron will randomly select 3 players, who will explode soon. A fire will spawn from each explosion (for total of 3 fires). The fires will slowly chase raid members and may switch targets on the way. Used during all phases.

Flame Suppression (Phase 1) - 60 seconds after engaging, Mimiron will flood his chambers and douse all currently spawned fires.

Frost Bomb (Phase 2, Phase 4) - Spawns a Frost Bomb in one of the triptychs of the room. The Frost Bomb will grow for several seconds and then explode, dousing all flames in that triptych and knocking players back.