Originally Posted by
Squirl
You should have used it on 10m too. Tank vengeance makes it insane on either difficulty. The priority is just 4 > 3 > 2 > 1. You can use other abilities while channeling 4. If you can, line it up with Snipe (Hisek buff) for even more damage.
The way we do it, the other tank tries to hold both bosses while the scorpion tank blasts away. Use Salvs if necessary. I don't know about BoPing as mentioned above. The auto attack hits for a load, and I assume BoP stops that as well as damage from 1/2. Get externals when you need them, but don't blow them all. Tanks will need something at the end (last 3 bosses) just to stay alive.