Decades ago, Nintendo and SEGA were bitter rivals, competing with each other in the video game hardware business with their various consoles and multiple mascots. Eventually, SEGA discontinued their efforts in hardware and decided to primarily focus on creating software.
While the company had some competition with Nintendo in the past, they weren't afraid to put future SEGA titles on their systems. Of course, this included one of their most famous properties, Sonic the Hedgehog. Takashi Iizuka, head of Sonic Team, explained that they decided to develop for Nintendo systems because that's what all the Sonic fans were playing.
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