If you wield a humanoid, and hit another humanoid with said improvised weapon, would both the weapon and target take damage?
Weapons don't degrade when using them unless the target has rules stating otherwise, but I assume that is because weapons have a default hardness that protects them from normal use. I find it difficult to believe that if an Ogre slams a human into an elf as a club that the human wouldn't be adversely effected by being used in that manner.
Are there rules regarding this? If not, how would you manage this situation as a GM?