Sonic 1 Pixel Perfect is a ROM hack of Sonic the Hedgehog for the Sega Mega Drive / Genesis by JcFerggy and NovaWizard. The hack features new extended layouts and art, custom loops and tubes, dynamic palettes for the acts, and a complete new Green Hill Zone layout (with edited boss) as of the first beta release.

Sonic the Hedgehog Spinball, or Sonic Spinball (ソニック・スピンボール Sonikku Supinbōru?), is a pinball video game in the Sonic the Hedgehog series. It was originally released for the Sega Mega Drive/Genesis in 1993 and later ported to the Sega Game Gear and Sega Master System in 1995.The term "Spinball" is a portmanteau on pinball and "spin dash", a move Sonic performs. It, along with Dr. Robotnik's Mean Bean Machine were the only two Sonic games released to use characters and elements from the Adventures of Sonic the Hedgehog and Sonic the Hedgehog cartoons.

Sonic the Hedgehog (ソニック・ザ・ヘッジホッグ Sonikku za Hejjihoggu?) is a platform video game developed by Sonic Team and published by Sega for the Sega Mega Drive/Genesis. First released in North America, Europe, and Australia on June 23, 1991, the game is the first installment in the Sonic the Hedgehog series, chronicling the adventures of the titular character in his quest to defeat the series' antagonist Dr. Robotnik. The game's story focuses on Sonic's efforts to stop Dr. Robotnik's plans for world domination, release the animals Dr. Robotnik has trapped, and collect six magical emeralds known as the Chaos Emeralds.Development of Sonic the Hedgehog began in 1990, when Sega ordered its AM8 development team to develop a game featuring a mascot for the company. After a hedgehog was decided on as the main character, the development group was renamed Sonic Team.Sonic the Hedgehog received positive reviews from critics, who praised the game's visuals and its sense of speed. It was commercially successful, increasing the popularity of the Mega Drive/Genesis and establishing Sonic the Hedgehog as the company's mascot. Its success led to the development of subsequent games in the Sonic the Hedgehog series, as well as the creation of a media franchise of spin-off products featuring the character.

Sonic The Hedgehog: The Lost Worlds is a hack of Sonic the Hedgehog 2 by ExecByte. This hack features all of the zones that were cut from Sonic 2 during development. Some zones have been ported from the Sonic 2 Simon Wai prototype and then finished up, and some have been created based on magazine pictures and information from interviews with people who worked on Sonic 2.

Sonic the Hedgehog refers to the Sonic the Hedgehog video game series released by Sega, and starring its eponymous mascot, the video game character Sonic the Hedgehog. The video game series is the primary product in a multimedia franchise, including products in a wide range of media.