I don’t know about you, but growing up I always played rock-paper-scissors with just three weapons … you know, the three in the title. But my wife is French, and as Wikipedia explains:

Similarly, the French game “pierre, papier, ciseaux, puits” (stone, paper, scissors, well) is unbalanced; both the rock and scissors fall in the well and lose to it, while paper covers both rock and well. This means two “weapons”, well and paper, can defeat two moves, while the last two weapons can only defeat one of the other three choices.

So I have questions for you.

1. There is a weapon in the French version that should never be used (in an optimal strategy). Which one is it and why?

2. Is it possible to add one weapon to rock-paper-scissors without rendering one weapon inferior to all the others? If so, give an example; if not, show why not. (Fans of The Big Bang Theory know it’s possible to add two.)