Originally Posted by
BobGnarly
Yeah, what I did is grouped my slaves at the bottom of the stairs (this is very important - with this you can just ignore the frost debuf as it gets cleared when he runs to the forges) with my tank about 1/2 way up the stairs.
Bloodlust right off and concentrate on the boss (forget adds for now, unless you can do high-damage single target attacks that are also aoe like chain lightning). After he goes to the first forge, kill the adds, heal up and wait. Repeat and win.
When he throws a boulder, since they're all grouped up, just strafe them all one way or the other. I get the impression that a lot of people don't have the ability to strafe the team independently of the tank. I consider this crucial for boxing the more mobile encounters and use it all the time. With this ability you will find it much easier to avoid the boulders.