I killed him twice today, he keeps spawning right outside the first room of Dragons near the zoneline to Draniks. He dropped the Mask of the Spellbound each time.
Heals himself throughout the fight, but aside from that is a fairly non-eventful encounter. I killed with a 58 rng / 54 beast/ 53 chanter + mercs - basically went afk while everyone hacked away for a couple minutes.
UPDATE - Checked my parse and have him for 51K HP (including all his heals)
Edited, Sep 3rd 2013 2:27pm by bhildebr