If you were to look at the Pokedex for a slot in which you haven't seen a Pokemon, you'd basically see a black-and-white question mark. This was actually not the originally-intended "missing Pokemon" sprite: rather, it was simply two large, white question marks. The data for the latter is still in the game, but you would need to use a cheating device to get to it.
Submitted By: KeyBlade999
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