On level 10 you will come to a mini-game on a Zero G Basketball court. You must beat the high score or tie it to move on to the next level. All I did was start the game, jump to the very front wooden platform, shoot 20 goals at level 1, wait, at level 2 shoot 21 and wait, level 3 shoot 22, wait, level 4 shoot 23, and so on until level 6. Complete that level and you will unlock this achievement. Don't bother getting multipliers.

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