hum, the group of 4 mobs can be pulled separately from the boss. you shouldn't have to fight them together. Just make sure you're round the corner when you pull the group, and they will run to you.
As for the disorient you get during the mage boss fight, well someone said already. The easiest is to set your "Interact With Target" key.
Press your IWT key, your toons will start running towards the boss. Then prass the back key slightly and they will all stop, facing the boss, ready to pewpew
Good luck
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