This guy is buggy as hell. We fought him once (probably after someone else's try) and the adds and he locked, but then it took several minutes before he merged together.
On a second pop (after winning the first) it locked up while the adds were split and all of their health was locked both at 60 and 20. If you're going to do him, be prepared for the script to bug out for several minutes during the split and waiting for the pieces to join together, and to take that beating for awhile.
Edited, Aug 4th 2014 12:34am by yaldin1