Sega

From Zelda Wiki.org

Sega is a video game development company, currently making both cabinet arcade games and game console software. They were once the famed rival of Nintendo back in the late 80s and 90s, but formally left console-development in 2001, and now even develops software for Nintendo systems.

Sega's mascot, Sonic the Hedgehog, appears alongside many Nintendo characters (as well as Konami's Solid Snake) in Super Smash Bros. Brawl.