Bare Knuckle II is a Street Fighter II-style fighting game for the Sega Genesis. It was developed by Sonic Team and published by Sega. The game was initially released in Japan in beta form in 1990. It was later released in English as Sonic the Hedgehog 2 for the Sega CD. The game is a two-dimensional side-scrolling adventure game with a fighting role. The player controls Sonic the Hedgehog, who uses punch and kick attacks to fight off enemies. The game features an extensive story mode, with different levels, bosses, and unlockables. The game also includes a number of unlockables, such as costumes, soundtracks, and characters.