Ran into him last night (literary lol) and wasn't prepared, he took out my Herald rather fast and I had him down to about 1/4 Moral/Health before I expired ;)
I came back fully buffed and with a better weapon than the 1h sword & shield I had been using...a very nice halberd and exacted my revenge. Had just hit lvl 19 with a non-tweeked toon using only quest rewarded gear. (human Captain)and still felt the fight was challenging, thought the higher dps weapon made most of the difference ;)
Was a fun surprise to see this beast suddenly appear in the darkness and shadows of the Blackwold Headquarters. Met him at a small entryway on the East side of the complex. (26.7s 43.8w)
Good luck & Happy Hunting!