Sonic the Hedgehog 「ソニック・ザ・ヘッジホッグ」 is an 8-bit version of the popular Genesis game Sonic the Hedgehog released with just a 3 month gap. It was also built into several Master System II systems in Europe. It was also the last game released for the Master System in North America.
The Master System version of the game has seen a re-release on both Wii and 3DS Virtual Console platforms. The Game Gear version has an appearance in Sonic Adventure DX as an unlockable game, as well as being included in the compilation disc Sonic Mega Collection.
The plot mostly remains unchanged from its Genesis/Mega Drive counterpart; Sonic has to travel through the South Island in order to take it back from Dr. Robotnik. He can also collect hidden Chaos Emeralds throughout the levels. An alternate ending is unlocked when all of them have been collected.