Everyone's been to the fair, right? The state fair? The county fair? A travelling carnival? Chuck E. Cheese's? If so, you've more than likely seen (if not played) some variant of the popular game colloquially known to me as "Whack-a-Mole" or by its more obscure moniker "Mole Whack-Em".
For those who haven't enjoyed this passtime, the rules are simple: artificial mole-shaped puppets pop randomly out of roughly mole-sized holes cut into a game board. The player, holding a mallet, tries to strike (or "whack") the artificial moles as quickly as possible since their appearance is timed and, if left unwhacked, they will disappear into the dark belly of the game board whence they came.
A simple game concept, and great fun for all.
Now, consider a version of "Whack-a-Mole" in which the mole-shaped puppets pop up, but do not recede if they are not struck.
Additionally, consider that our hypothetical version of this game has an infinitely large (or at least some very large) domain of potential mole-shaped puppets.
Finally, assume that the game board is free to grow as you play, allowing for an indefinite number of visible mole-shaped puppets at any given time, all waiting for you to clobber them with your mallet.
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