I've only managed to play Grznyr for one high-flaying epic tier session. Gnolls are pretty B.A. and I just couldn't get the concept out of my head, so I rolled him up for this game using gnoll rules from Dragon magazine.
Grznyr probably had a pretty typical gnoll upbringing, learning to become ruthless, vicious, and tricky. I'm sure he was some kind of bandit before he fell in with less evil-minded adventurers who could tolerate his mannerisms. Maybe his tribe was killed off or something; if they tried to exile him, then they're surely dead by now. After all this adventuring, him and the party are Epic legendary sorts of dudes, being all awesome and stuff, doin' thangs.
As is common for gnolls, Grznyr cares little about most people's welfare, and takes what he wants if it suits him. The only people he cares much about at all are the other PCs in the party because they're basically like his surrogate pack at this point, though he seems to be a big jerk to them (it's all about posturing to settle the pack heirarchy and stuff). In the height of gnoll fashion I expect he has very rag-tag armor scavanged from all sorts of folk. Gnolls also age very fast, so he's probably a lot younger than other party members and a lot closer to dying from old age very suddenly after finishing their epic desitny quest thing, theoretically.
Dates played: fall 2008 for a session
Class levels: ranger 21, pathfinder, deadly trickster
Sweet traits: He's a two-weapon ranger, so he's surprisingly tough for a striker, and he just stabs all over the place in combat. He's got some neat gnoll feats that let him track by scent and do great feats of ventriloquism. Basically he's this wild and vicious melee guy swinging swords around like a crazy hyena-man.
Sweet gear: The main things are probably his +4 lifedrinker bastard sword and +5 magic scimitar that he dual wields. I had to take a handy haversack, of course.