you could use the spoiler Ctrl J to jump to a different area on the map after you saw he was gating to you (the spell that looks like a gate appear). he won't cast any spell (like imprison) you or anything. he might chase after you if you go into a different zone but do the same thing and he become 'harmless' and i use that word with caution, damn the man i kept hitting him for 40 dmg and the bastard wouldn't die. However, he won't follow you to hell so you don't have to worry about making new Grizz's scimitars in hell
i dunno which weapons would be better than that sword, any suggestion?