Thorim

The fight against Thorim is split between two phases. The first one requires you to fight your way to Thorim by fighting multiple types of trash mobs in the Arena, the second one will let you face Thorim himself.

The first part of the fight is split in 3 mini-phases (Jormungar > Iron Dwarves > Hallway). Thorim will use a few abilities during the arena event, do not bother attacking him because he is protected by Sheath of Lightning

Thorim Health: 20,000,000 HP

	Stormhammer	Throws a stormhammer, dealing 2451 to 2551 damage to an enemy, knocking down and stunning the target for 2 sec, and causing a deafening thunderclap to all enemies nearby the target. 100 yd range, 0.5 sec cast
	Deafening Thunder	Inflicts 4625 to 5375 Nature damage to enemies standing in close proximity to a Stormhammer strike, increasing spell casting times by 75% for 8 sec. 50000 yd range, Instant
	Charge Orb	Charges a nearby orb with electricity. Causes Lightning Shock - Inflicts 2831 to 3169 Nature damage on a nearby enemy.
	Berserk	Empowers allies with the full might of Thorim. This spell will increase damage done by the adds by 500%, casting speed by 200%, and their health by 300%. This is an enrage ability casted on all the adds if players take more than 5 minutes to reach Thorim at the top of the Arena.

Jormungar & Mercenaries You will first encounter a Jormungar Behemoth and a few NPCs from the opposite faction fighting in the Arena.

Jormungar Behemoth

Acid Breath

Spews acidic bile at a target and nearby enemies, inflicting 12000 Nature damage and 1500 additional damage every 2 sec. for 18 sec. 50 yd range, 1 sec cast

Captured Mercenary Captain

	Devastate	Sunder the target's armor causing the Sunder Armor effect. In addition, causes 50% of weapon damage plus 90 for each application of Sunder Armor on the target. The Sunder Armor effect can stack up to 5 times.
	Heroic Strike	A strong attack that deals 3938 to 5062 additional Physical damage.

Captured Mercenary Soldier

Barbed Shot

Fires an arrow that pierces an enemy's flesh, inflicting 4513 to 4987 Physical damage and causing 500 damage per 3 sec. for 12 sec. 45 yd range

Iron Dwarves Event Once the NPCs and the Jormungar are dead, a lot of constructs (melee, casters, and healers) will jump into the arena from the stands and you will have to take care of them with only one part of your raid while the other part runs through the hallway on the left to reach Thorim.

Dark Rune Acolyte

	Greater Heal	Calls upon Holy magic to heal an ally for 94500 to 115500 Health. 40 yd range, 2 sec cast
	Holy Smite	Smites an enemy, inflicting 7650 to 9350 Holy damage. 50 yd range, 1.5 sec cast

Dark Rune Champion

	Whirlwind	Attacks nearby enemies in a whirlwind of steel that lasts 2 sec. and inflicts normal damage plus 50.
	Mortal Strike	Inflicts 250% weapon damage and leaves the target wounded, reducing the effectiveness of any healing by 50% for 5 sec.
	Charge	Charges an enemy, inflicting normal damage plus 75 and stuns the opponent for 2 sec. 8-25 yd range

Dark Rune Commoner

Low Blow

Lands a cheap shot on an enemy, inflicting Physical damage and reducing the target's damage dealt by 3% for 20 sec. 5 yd range, Instant

Dark Rune Evoker

	Runic Lightning	Strikes an enemy with a blast of runic lightning, inflicting 7875 to 10125 Nature damage. 150 Mana, 45 yd range, 1.5 sec cast
	Runic Mending	Heals an ally for 18500 to 21500, then heals for an additional 6000 every 1 sec. for 15 sec. 280 Mana, 40 yd range, 2 sec cast
	Runic Shield	Surrounds the caster with a runic barrier, absorbing 120000 magical damage and reducing all Physical damage taken by 50%. 330 Mana, 30 yd range, 0.5 sec cast, 6 sec cooldown

Dark Rune Warbringer

	Aura of Celerity	Increases nearby allies' melee, ranged, and casting speed by 20%. Instant
	Runic Strike	Strikes at an enemy with an electrified weapon, inflicting Nature damage equal to weapon damage plus 1000. 5 yd range, Next melee

Iron Honor Guard

	Cleave	Inflicts 150% of normal melee damage to an enemy and its nearest ally.
	Shield Smash	Inflicts 7400 to 8600 Physical damage to an enemy, stunning it for 3 sec.
	Hamstring	Inflicts 50% weapon damage to an enemy, reducing its movement speed by 60% for 5 sec.

Titanium Stormlord

Cyclone

Attacks nearby enemies in a whirlwind that inflicts 100% weapon damage as Nature damage.

Hallway Once the NPCs and the Jormungar are dead, a lot of constructs (melee, casters, and healers) will jump into the arena from the stands and you will have to take care of them with only one part of your raid while the other part runs through the hallway on the left to reach Thorim.

Dark Rune Thunderer

Lightning Brand

Shocks the target for 3500 Nature damage to the target, and increases Nature damage taken by 40% for 20 sec. 8 yd range, Instant

Iron Ring Guard

	Impale	Deals a vicious attack that causes the target to bleed profusely until healed past 90% of its maximum health. Deals 1750 damage every 2 sec. for 1 min or until removed via healing. 5 yd range, Instant
	Ravage Armor	Reduces the target's armor by 5%. 8 yd range, stacks up to 20.
	Whirling Trip	Knocks down nearby enemies, stunning them for 2 sec. and inflicting increased weapon damage.

Runic Colossus (Mini Boss)

	Charge	Charges an enemy, inflicting 6938 to 8062 Physical damage and knocking the enemy back. 8-40 yd range, Instant
	Runic Barrier	A shield of runic power surrounds the caster, reducing all damage taken by 50% and inflicting 2000 Arcane damage to attackers. Instant
	Smash	Deals 37000 to 43000 Physical damage to all enemies within a 10 yard cone in front of the caster. 3 sec cast, 2 sec cooldown

Ancient Rune Giant (Mini Boss)

	Rune Detonation	Immobilizes a target with a runic ward that detonates after 4 sec to inflict 11250 to 13750 Fire damage around the target. 60 yd range, Instant
	Stomp	Inflicts 12250 to 15750 Physical damage to nearby enemies and knocks them back. 10 yd range, Instant

As soon as you reach Thorim at the end of the hallway, he will jump in the Arena where the first part of your raid is and will engage them.

Thorim Health: 20,000,000 HP

	Touch of Dominion	Subjugates the target to the will of Yogg-Saron, weakening it yet conferring a subtle control. Reduces Thorim's health and damage by 25% if the raid reaches him after the 3 minutes hard mode timer.
	Chain Lightning	Strikes an enemy with a blast of lightning that inflicts 3700 to 4300 Nature damage. The bolt will arc to additional nearby enemies, inflicting 100% more Nature damage to each successive target. 150 Mana, 100 yd range, 0.5 sec cast
	Lightning Charge	Absorbs a torrent of electrical energy, inflicting Nature damage to enemies in a cone between the caster and the power source, and increasing the caster's melee damage and attack speed by 15%, and Nature damage dealt by 10%. 100 yd range, Instant
	Lightning Charge	Absorbs a torrent of electrical energy, inflicting 13875 to 16125 Nature damage to enemies in a cone between the caster and the power source. 150 yd range, Instant
	Unbalancing Strike	Inflicts 200% weapon damage and leaves the target unbalanced, reducing their defense skill by 200 for 15 sec. 8 yd range, Instant

If you reach Thorim within 3 minutes, he will not be affected by Touch of Dominion and have 25% more damage and health. Additionally, he will be helped by his wife Sif. You cannot kill her, she will just attack the raid while you're fighting Thorim.

	Frostbolt Volley	Inflicts 9000 to 11000 Frost damage to nearby enemies, reducing their movement speed by 50% for 4 sec.
	Frost Nova	Inflicts 9425 to 10575 Frost damage to nearby enemies, immobilizing them for up to 6 sec. 2.5 sec cast
	Blizzard	A rain of ice moves around the room, dealing 3282 to 4218 Frost damage every 1 sec. for 10 sec. and lowering the movement speed by 65%.