I found the Battlerager prestige class in Races of Faerun, along with an entry for "spiked helmet" in the equipment appendix. The spiked helmet does 1-3 damage, x2 on a charge, with 0 reach. The damage and the size of the spike in the accompanying illustration fall short of what I had in mind for Pwent--- his helmet spike is described as adding a foot to his height! Pwent's armor is described as "ridged", not spiked (I'll concede the difference is only nominal in terms of game effect.) The question is, what type of spiked armor would it be? Banded mail? Studded leather? In terms of feats, I'd say his, 'shake 'em to death' schtick would be best replicated by something like the Knife Fighter (i may be getting the name wrong--- it's a regional feat from one of the FRC books) feat that allows attacks with a light weapon while grappling without the -4 penalty.