Free game, play all you want, you never have to pay anything
TwoThree
Very simple arcade. You point the gun to numbers falling from the sky, and shoot numbers two or three from your gun. If you shoot 2 with 2, it explodes. If you shoot 3 with 2, the one remains and falls to the ground spelling doom, because you don't have anything to shoot ones! I especially dislike 17. Have you tried to shoot down 17 with 2 and 3? I have.
I can see how this skill can be useful in real life. All you need is a real life number gun and numbers falling from skies.