Half of cities in the game are 'in' and half are 'out', according to the secret rule, i.e. the 'in' cities all have something in common that is not true of the 'out' cities. (3 'in' cities are given when you click START to get you going.) The order that you click on the 'in' cities does not matter; just avoid the 'out' ones. For each shot that you get in, another 'in' city will come back at you to help you make your next selection. Think carefully about your shot selection, or you will lose the rally! How long can you keep the rally going for? (The secret rule is revealed if you get to the end, then click ~~~CLICK TO FINISH~~~ to win the game.)
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