You will want at least 2 places laid out for your tank and raid to move between.
About 30 seconds into the fight two 'totems of silence' will spawn on your raid. This is when you will want to move to your second point. I believe the totems spawns every 45 seconds so just move to your next point once you see them pop. Standing too close to the totems will cause you to be dazed. You have to be about 20 meters away to avoid it. Keep the two detrimentals cured and this fight is easy.
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Challenge Mode
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There is only one major difference in the strat for CM. When killing the adds from the previous encounter of Hragdold your raid will be given a 'diseased pox shard' and is critical to the success in this fight.
Every 30 seconds a raid member will be hit with a uncurable arcane, Arcane Affliction, that will last for 20 seconds. When this effect expires you will stun and AoE your raid if you are not provided with immunity from the pox shard.
The effect from the shard only lasts 10 seconds but the recast is 16 seconds. When the timer on the arcane effect reaches 5 seconds the person's vision will turn yellow so if they are paying attention to the effect time they can hit the pox shard when their screen turns yellow and this effect will not do anything to the raid.
The rest of the fight remains the same, avoid the totems, cure the curse and kill him.