Short Tactics
This instance is a position fight. If players are too far from Yakhmar he one-shots them. The adds will target the 4 toons furthest as away from Yakhmar (within his range). Two tanks are enough on Yakhmar who starts the fight by charging him and they never change position at all during the fight. No debuffs, pre-heals or anything on Yakhmar from a toon that is not one of the 2 main tanks first couple of seconds. Because he also one-shots (will get messy with any movement) if an aggroholder is not hugging him.
At 75% Yakhmar will start casting frost bolts. These are 4 bolts that emerges travelling towards his head. If the raid is positioned to his side as in the picture below it´s ok to only take the 2 bolts coming on that side (3 bolts to be safer) the fourth splashing the opposite side will not affect the raid.
Important timing on frost bolts: To not have bolts at the same time as add spawns, the raid has to make sure that Yakhmar is not reaching 75% at the same time. Stop dps at about 78% on Yakhmar, wait until a wave of adds is killed and then burn Yakhmar down to 75%. As adds and frost bolts are on timer it will later work well to tank adds, heal up and run to catch bolts and repeat to take adds. Another class can also take the bolts, with frost damage protection and nice constitution (raid leader announces what to do).
Add tanks: Max mitigation as the adds do physical damage only. But also some protection is needed because of frost bolts that normally is caught by add tanks too, T4 gear as Fearless is nice or if you don´t have it use some Black Dragon big piece for example. Priority is on mitigation and the adds can crit high.
They Hunger: This is a slow cast that Yakhmar does and just before he finishes casting it everyone must use active blocking (meaning press X button). Hold X until you see the 3 second buff time out then release. It will drain mana/stamina doing so and you will die if you have no mana/stamina during They Hunger.
This is the start position before the 2 tanks charges Yakhmar.
Yakhmar team positioning after first wave of adds:
It´s not a complicated fight. Once the raid team is used to time buffs/heals it´s all about repeating the same thing until it´s done.