'Spoofing' is an old, old sport. It consists of trying to guess what your opponent is going to do, and then doing the opposite. The only equipment you need is a hand (one to each player, that is).
The two opponents hold their right hands in front of them, bunched into fists. Simultaneously, they raise and lower their fists three times before opening their fingers into any one of three possible mimes, at exactly the same moment:
(i) Paper. All four fingers are extended together,
(ii) Scissors. The first and second fingers are extended to make a 'V shape.
(iii) Stone. The fingers are left as they are, bunched in a fist.
Each mime is able to 'defeat' one of the others. Scissors obviously score over Paper, because they can cut it; but Paper scores over Stone because it can wrap it up. Stone scores over Scissors, because it can blunt them.
Every time a player defeats his opponent, he scores a point. If the mimes are the same, of course, nothing is scored. The winner is the first player to reach ten points.
A judge may be needed to watch out for cheating. By lagging a split-second behind his opponent, a player may see what is being shown, and change his mime accordingly. Anyone caught cheating loses three points.