I introduced boozehounds to my game a couple of sessions back, and the players got a kick out of them. They suit the whimsical nature of Tunnels & Trolls, and the notion that players should at least be chuckling as their beloved characters are torn apart.
Boozehounds have an insatiable lust for alcohol. They can smell it at great distances and will track it relentlessly once they've gotten a whiff. A typical boozehound has a monster rating of 30, but for each round that they spend drinking booze, their MR increases by 10, to a maximum of twice their starting MR. For old-school D&D style games, they have a typical hit dice of 2-3, and a 1d6 bite, but their HD increases by 1 each round they spend drinking, to a maximum of twice their starting HD.
The drunker they get, the nastier they become, so it's best not to let them get a snoot full!