Just took this guy down on Prexus, 80 cleric, roughly 12khp, 2.5k ac (dont laugh, I know she's pretty weak still). Had a 63 cleric friend there mainly to keep me company while waiting for him to spawn, and an 80 wiz friend came as backup in case something went wrong. It was mostly a joke. Max hit on me was 973, with somewhere around 350 being the average hit. Wizzy nuked once, maybe twice, no heals needed. Ended fight at about 96% hp (had Vow of Valor up tho).
Killed the regular named 3x before the Fabled spawned, altho the server crashed once which caused the named to spawn much faster than it normally would have. 42 minutes seems to be the correct timer.