Phase One: Gather up, have one designated ranged DPS shoot down the frost orbs above to form permafrost on the ground.
Nerubian Burrower adds will spawn in phase one and they stack an Expose Armor debuff on their tanks, up to 9 stacks which increases physical damage taken. These need to be tanked on the permafrost or else they will burrow and heal back to full. The raid should have 2 off tanks (on 25 man) to pick these up. By the time Anub'arak burrows, there should only be 4 of them up; 2 on each tank. They should be killed during phase 2, when the raid has nothing else to do. For groups with only one tank for the burrowers it is advisable to just kill them as they spawn to reduce offtank damage taken.
Phase Two: Anub'arak will burrow approximately every 90 seconds, starting phase 2. He will pursue a random target with spikes throughout the phase and when he reaches them he will cast Impale. The spikes will gradually speed up until they hit the target, or hit a patch of permafrost. Standing on the permafrost (or being on the other side of permafrost from the spikes) will enable you to avoid the impale, but the permafrost will despawn. After a few seconds, he will select another target. Agro dropping abilities (Feign Death, Vanish, Divine Shield, Iceblock) will cause the spikes to change target, but their speed will not be reduced.
Swarm Scarabs will spawn rapidly, scarabs have little hp, start with 20k threat on a random raid member. They all stack the same nature damage debuff on their targets and should be range kited and killed, or killed by melee not being chased by them. They can be slowed by permafrost to gain more distance. After about one minute Anub'arak will surface and begin phase one again. He keeps threat from phase one.
Phase Three: It is advisable to kill off any adds currently active before pushing Anub'arak under 30%. He will not submerge or summon any more adds at this point (on normal mode). Anub'arak needs to die very quickly after hitting 30% as you will not last long under the effects of leeching swarm. It is not ideal to top off raid members as they will then be taking full damage from the leeching swarm, healing Anub'arak and prolonging the phase. Instead you will want to keep people as low as your healers feel comfortable with (recommended under 50% hp) inorder to minimize the healing Anub'arak receives (Anub'arak will be being healed for ~60,000 HP a second if the entire raid is at full HP on 25-man mode). Beware of people getting gibbed by penetrating cold. The main tank (and offtank if adds are still alive) will need to be topped off and people with penetrating cold will need some healing. Anub'arak does not have any other tricks and will die upon reaching 0% HP. NOTE: Anub'arak can be healed above 30% by the leeching swarm. The swarm will not turn off once activated. It is recommended to save Bloodlust for phase 3.
makes me wanna play mortalkombat again 
