Yūzō Koshiro (古代祐三, born 1967) is a video game music composer, sound programmer, and the president of the video game company Ancient Corp. Koshiro is one often regarded as one of the most influential innovators in chiptune and video game music, creating some of the most memorable game music of the 1980s and 1990s. He is best known contributing for games such as Nihon Falcom's Dragon Slayer and Ys series, as well as Sega's The Revenge of Shinobi and Streets of Rage series. The soundtracks for the latter have been cited by some to be ahead of their time.