If you hold an item in your hand other than food or drink and you left-click a monster, it passes the turn. If you are holding food or drink, it feeds it to the monster. If you are holding a fungus it passes the turn. I can't feed a monster a Potion of Healing, but I definitely fed it a Potion of Steeling. I can maybe understand the flavor of having the ability of giving food to a monster. (There should be a Steam achievement for feeding Dredmor!) But I don't think it should pass the turn if you are holding a non-consumable or a fungus. It should just attack the monster! I'm currently playing with Fungal Arts (the RC5 version) and mushrooms are all over the place. Many times so far I've been fighting multiple monsters (like in a zoo) and I'm just repeatedly left-clicking to attack them, but at some point I pick up a mushroom and then all my left-clicks do nothing! I spend the next couple of turns ineffectively trying to shove a mushroom down a monster's throat and getting attacked in the process. I really don't think you should be able to feed monsters. I understand that you can do this to pets, and they are currently programmed in the same way as monsters in this regard. Feeding a pet should be allowed, but not monsters. At a minimum, non-consumables shouldn't cause you to just pass the turn when they are in your hand and you click on a monster. And why are fungus treated as non-consumables in this way?
An addition to this-- if you're holding an item, you can attack monsters normally (animation included). But for some reason the game does not let you use levers. Opening doors works though.
