I would like to propose that backstab work when the unit on the opposite of the unit being attacked is not on the same team as the unit being attacked (and isn't incapacitated which I think currently would just be being stoned).
(Currently the unit on the opposite side must be on the same side as the unit doing the attacking.) I think this is conceptually better as the other unit is being used as a distraction and any hostile unit should be able to provide that. I think the overall effect will be small, but I think providing some other interaction between players in multiplayer games is an improvement to the game. Assuming the response by other developers is positive, I would work on making a patch for the 1.1 branch.
