How play: When you click the green flag, nine numbers will go by one by one. They will be the numbers 1 - 10, but one will be missing. Then, you have to click on the number that you did NOT see. So, if these were the numbers you saw: 7,3,4,6,1,9,8,10,5 then the correct answer would be 2 (because the 2 never went by). This is a very simple game, but it can be surprisingly difficult (at least in my opinion).
Updates: 17 May (Scratch day!) - Shared original game. 17 May (Later that day) - Cool thumbnail. 18 May - Added link to this game in signature. 18 May - Added menu button on win/lose screen.
