Street Fighter II (18 Different Platforms)
OK, OK, I admit that I'm cheating here a little. If you were to count only the original Street Fighter II: The World Warrior, then it would have only been ported about 12 times, according to its Wikipedia page. But, if you include the many different releases of the game, including Super, Hyper, Turbo, Super Turbo, HD Remix, and more, the number jumps up quite a bit. Believe it or not, Street Fighter II was ported to consoles such as the ZX Spectrum, Commodore 63, Atari SI, and Amistrad CPC. This, in addition to its many different arcade releases on many different Arcade platforms, made it one of the best-selling and most ported games of all time.