Once you get to this guy, you will have to clear a room with a lot of copper, silver, and gold golems. Royal pain. Keolyx is all the way in a deadend with no room around him to rogue drag a mage and coh, so that option is void.
loc -602, -803, -637
The battle-
Tank pops a disc and build aggro, then everyone else unloads on Keolyx and it should be over quite quickly.
Keolyx has about 470k hp's and hits consistently for 4.7k. he seemed to tripple.
Uneventful fight for what it takes to get to this guy, really, bule con to 85 and nothing special on drops along the way.