He's easy like the rest of the Fableds. You can do it a few ways. All you have to do is have a character have agro on him. Once he has a player on his agro list then his regen returns to a killable state.
You could set up a def warrior with a few clerics, you could warp a character in, take a hit then succor and FD or fade or something, you could have a monk get up for a sec then fd, then get up every 6-10 seconds. You could have a cler,sk,brd,nec or anyone with a DA item warp there and hold agro like that, paladin with da hammer while you GK him. Much much more...
I hope this helped out.
To be a good cheater (re: not a good speller) you have to be an exceptional EQ player.
edit: I forgot about bane weapons for him. I will see if my way works, probably not, but it will definately work on all other lvl 75+ fabled.