Basically, you choose odds or evens and remark "Once, twice, three, SHOOT!" each
player either holds out a closed fist, 1 finger, or 2 fingers, therefore the total can either add up to 0, 1, 2, 3, or 4. If it is 0, no
player wins. If it is even (2,4) the evens
player wins and if it's odd (1,3) the odds player wins.