There is a nearly finished game of Panel de Pon within the game's code. When loading Pokemon Puzzle Challenge onto a Game Boy or a Super Game Boy, at the Game Boy Color Only warning screen, pressing A 24 times, followed by B 24 times, the game will then start. It's possible to access the Game Boy Color warning screen on the Game Boy Color by pressing up twice, follow by right 4 times, down once, left 10 times, up 4 times, right once, down 6 times, and then pressing B at the game's title screen.