King Rastakhan is a four phase encounter that starts out with three adds that must be killed to actually fight Rastakhan. Siegebreaker Roka casts Meteor Leap, make sure you soak this as a raid. Prelate Za’lan casts Seal of Purification at a DPS member, make sure you don’t stand in this. Headhunter Gal’wana casts Grevious Axe at 3 random players on Mythic. These targets need to be topped as quickly as possible. During this, Rastakhan will cast Plague of Toads, Greater Serpent Totem, and Scorching Detonation. The toads and serpent totems should be avoided at all costs, and the Scorching Detonation you will want to use a healing cooldown for.
Once Phase 2 begins you will want to position yourself on the edge of Bwonsomdi’s Aura of Death to heal the tank who is currently tanking Bwonsomdi. Spread out for Plague of Fire. Dodge Plague of Toads. If you are the only shaman in your raid, use Tremor Totem on the first Zombie Dust Totem, and then skip the next, using it again on the third totem. Death’s Door need to be placed where ever your raid leader decides. You can place them near the door to make the next Bwonsomdi phase easier by creating a barrier, or you can place one near the middle of the room to allow melee going down to remove their Deathly Withering if you are going for the non-cheese strategy. Once your barrier of Death’s Doors or your single drop off point is created, drop all Death’s Doors on a wall or in a corner for the rest of the fight.
When King Rastakhan reaches 60% health remaining, Bwonsomdi will pull half the raid (closest raid members to him) into the death realm. In the death realm you will always gain stacks of Deathly Withering and will have to dodge Dread Reaping. If you chose to do the cheese barrier strategy, simply stand behind the barrier and heal people after their Caress of Death wears off. Run away from Bwonsomdi when he casts Inevitable End. If you are not chosen, simply heal the remaining raid members from damage done by Scorching Detonation and Withering Burst, and soak the missiles spawned by Seal of Bwonsomdi.
Once Bwonsomdi reaches 50% health remaining, the death realm group is sent back up to the realm of the living. From here King Rastakhan gains the ability Inevitable End and retains all his phase 2 abilities except for Zombie Dust Totem. Simply dodge the Dread Reaping coming from the Death’s Doors around the room and handle the rest of the mechanics like you did in the previous phases.
In the scenario you are not sent down to the death realm, swap EWT over to AV. If your group decides to do the cheese barrier Death’s Door strategy, consider swapping Graceful Spirit over to WRT if you are the healer going down to the death realm to prevent people from mass triggering Withering Burst when Bwonsomdi casts Inevitable End.