Not sure if he wanders, but i just ran into him @ loc: -4905.80, 762.78, -197.74
Solo'd as 72 necro. Rediculously easy. Had healer merc, but didnt need him. He healed twice i think, and was an overkill. I would say he has 100k or so HP. Loaded up 8 dot's and fight took about 3 minutes, didnt parse though. Dropped decent sword, talisman, and head

Edge of the Taskmaster
Head of the Taskmaster
Old Worn Talisman