If you're achievement hunting, here's what I was looking for.
* Immune to changes in attack speed
* Immune to changes in run speed (I assume also immune to root, but I didn't try)
* When pulled, his two assassin guards and the higher level mobs in the room will assist
* I didn't look at max hit, but it wasn't too high, somewhere around 300, I think
I was able to duo him at level 60 (Luclin era on TLP) with just a bard and druid, ~100 AAs and Luclin era raid gear in most slots. I was able to separate him by pulling to the Shadow Haven zone line, using a combination of Highsun and zoning to clear aggro, then zoning back in to tag and eventually get him by himself. It was a fairly long fight (not a lot of DPS with those two classes), but the druid easily kept the bard alive using druid-CH (Tunare's blahblah) and refreshing DoTs as they wore off. Epic click had to be refreshed twice during fight to give you a better idea of fight length.