Yeah its called bringing a friend to be your blocker lol
Otherwise just bring rings of recoil, and use magic for accurate hits, as he heals everytime you hit a 0, so if your low combat and using melee, its difficult.
I had 6 def and 35 magic when i did this. You can safe spot behind the coffin, my second try (forgot the stake first try) i just bit the damage, which really wasn't much. 2nd tier magic spells hit him like a truck.