Cataclysm Heroic Dungeon: Blackrock Caverns

Trash:

• No AoE pulls. Ranged mobs can be LoS'd (Line of Sighted).
• Raz the Crazed will kill most trash so pause before pulling that crazy trash. He appears after you kill the first boss.

Rom'ogg Bonecrusher:

• Clear mobs before pulling boss.
• Outrange his AoE by running away from him.
• For boss mechanics, think Terestian Illhoof of Karazhan.
• Chains of Woe will pull party to him and trap them. Then he will cast an AoE called The Skullcracker. DPS chains and free everyone so they can run out of range before the AoE hits.
• Wound Strike does 125% weapon damage, wounds them, and reduces healing by 25% over 6 seconds.
• Quake is a slam that deals AoE damage to nearby players. Largely inescapable and will require a heal through. This will also spawn adds that needs to be picked up and killed off. Tank may have to blow some major CDs due to healer strain.

Corla, Herald of Twilight:

• For boss mechanics, think Netherspite from Karazhan but with adds.
• In heroic, there are three dormant Twilight Zealots that have channeled beams on them. These beams stack a buff called Evolution. If Evolution stacks to 100 on them, they become a Twilight Drakonid that must be picked up and tanked. 

1. DPS stands in beam in front of the zealots and will start to stack Evolution on you. When you get to around 70 or 80 stacks, hop off and it will decay in about 15 seconds. If you stand in the beam too long, allowing the stack to reach 100, you will become a Drakonid that must be killed.
2. Tank and healer can help to stand in for beams when DPS needs to hop out. Tank would stand in for the melee DPS, and the healer for the ranged DPS.
3. Aura of Acceleration will increase movement and attack speed of Drakonids.
4. Her Fear not only fears the target, but does significant shadow damage. Luckily, it's just single target and can be dispelled. However, it must be healed through. Therefore, healer should not let DPS dip too much. 

Karsh Steelbender (optional):

• Clear the mobs (Conflagrations with Quicksilvers). Pull Conflagrations (one by one) up the ramp and kill them first, then DPS the additional Quicksilvers down. Conflagrations deal significant party damage, so it is important to deal with them first.
• If you decide to skip Karsh, Raz the Crazed may not come to clear mobs for the final boss. 
• Karsh cleaves, so everyone but the tank must stay away from his front. 
• Quicksilver Armor buff on the boss will render him virtually immune to damage.

1. To take this off, tank must drag him through the molten metal in the center (pillar) which flows from the ceiling.
2. DPS stay off the grating at the outer ring as much as possible.
3. For each second that Karsh is in the pillar, he gets a stack of Superheated Quicksilver Armor (it looks like a gold shield debuff icon) which reduces Quicksilver's damage mitigation properties but will increase damage to nearby enemies and do AoE damage to party. The stacks will wear off over time so he must be dragged back through again. ***NOTE: In heroic, when the debuff falls off, adds spawn. When an add dies, it leaves a fire puddle on the floor that melts his armor and causes AoE damage. If the adds die in quick succession, the AoE rises and healer will have a hard time keeping up. One strategy is to pull him in and out of the fire before the debuff expires. Another is to let his stack rise to 14 (that is if your tank and healer can handle it).

Beauty (optional):

• Four pups that can be killed individually, but heroic pulls the entire room.
• Do not kill Runty till the very end. Killing Runty causes Beauty to enrage.
• You can CC the adds with Fear, so you can pick off the puppies. With four puppies going, there is a lot of damage going out, so you may have to blow cooldowns.
• Berserker Charge will cause her to charge the furthest player away from her.
• Flamebreak is a knockback which also does fire damage to tank and melee. Tank her against a wall or rock.
• Magma Spit deals fire damage to random player which will do DoT damage every three seconds and explodes when removed, so do not dispel!
• Terrifying Roar, which is cut and dry AoE Fear (you can break out of this with abilities you'd normally use to prevent or remove fears). Clear trash outside of room so you don't accidentally pull trash with a fear.
• Abilities can't be countered.
• Magma puddles also appear, so these must be strafed out of.

Ascendant Lord Obsidius:

• Let Raz the Crazed get rid of the mobs, but he will end up dying. Only a couple adds will remain. *Note: if you opt to not kill Karsh, then Raz may not appear. 

1. Adds are CC'able and kiteable, so 1 or 2 DPS can kite these to keep them off the tank. They don't have an aggro table, so they will  attack whoever attacked them last.
2. Channels a healing debuff on target that will reduce healing received to zero.
3. Can't be stunned, feared, and DPS'd down, but they can be rooted, snared, and slowed.
4. Adds don't do a lot of damage, so DPS can take a few hits.

• Boss does switch place with one of the adds occasionally so watch out for this. He will drop all aggro, so tank has to pick him up fast, and DPS needs to find their adds and lock them down once more.
• Key to fight is fast target switching.
• Abilities:

1. Stone Blow does melee damage and has a knockdown.
2. Thunderclap is an AoE damage to nearby players and slows movement speed.
3. Twilight Corruption is a ticking DoT that is dispellabe.