[Duck of Doom]

Several questions regarding the Harm Pit Dungeon:

1) When you are fighting a monster in the Harm Pit Dungeon, and someone else plays a cards with negative bonus such as Baby (-5 to monster), do the card modifier get doubled too (-10 to monster in that case)? Does it count as a Card played "against the players"? It actually makes the kill easier even if it can have some adverse effects (gaining one less Treasure for instance).

2) Do cards played by the helper in a fight get doubled if he uses them to help the monsters (for instance a one shot item)?

3) Do bonus described in Monster cards (for instance a +4 against Clerics) get doubled too when played against the Munchkins (for instance with a Wandering Monster card) or only the level of the Monster gets doubled?