Well he must be important because somehow he got his paws on the Claw and Horn of Kazgaroth, possibly some of the most powerful artifacts in western Faerun, and last known to be in the Moonshae Isles per Doug Niles' books (might make a cool mod to explain how he got hold of them).
Uhm, the items don't appear to be *that* important. Kazgaroth's heart is a minor artifact, but we don't know what it does. His Claws and Horn aren't even artifacts, AFAIK.
I know that D&D 3.5 goes to level 20, and uses "EPIC" rules afterwards. is there and equivalent break-point on AD&D2.0?