It's the Pinky from Doom 64, as converted by Kaiser for Absolution, then Footman from Absolution for ZDoom/GZDoom (he also credits Orangewaggs and says other people he couldn't remember also helped), and finally SgtMarkIV for Brutal Doom 64. So it has the brightmaps from BD64, the shadow effect from Brutal Doom and the footstep sounds created by TheZombieKiller.
that's a big *** Pinky