You need two people on it, to be honest. You have a tank on Halfus - he can take every other one.
My guild was doing 10man Bastion of twilight. We were on the boss Halfus Wrymbreaker with the Emerald Whelps, Slate, and Stonebreaker. We started the pull by pulling Halfus and releasing the whelps and Stonebreaker. This was to slow his casting speed for us to interupt
Me as a rogue was placed on the boss so i was glyphed for Kick to make sure i could hit the interupts. I was only able to make like every other interupt due to i had the most fraction of a second between kick coming off CD and the boss casting Shadow Nova. I tried to kick when it when he first started casting to 50%. So glyphed i had a 8 second CD and wasn't able to make it. Any suggestions?