Gamefam developed and published Sonic Speed Simulator on Roblox.
The game is an officially licensed Sonic the Hedgehog title made in association with Sega of America. It uses Roblox Studio as its engine and combines platforming with incremental-game mechanics: players run through zones, collect rings and Chaos Orbs, complete quests, and improve their speed and jumping ability.
Sonic Speed Simulator began as a paid closed beta before becoming free to play. Its concept came from Gamefam founder Joe Ferencz, who pitched Sega on bringing Sonic to Roblox’s large, young audience. That partnership is why Sega is associated with the game, but Gamefam remains the developer and publisher named in the game’s credits and reference listings.
A common mix-up is to answer Sega because Sonic is a Sega franchise. Sega licensed and supported the project; Gamefam handled the Roblox game’s development and publication. The title also became notable for its unusually large launch and later billion-visit milestone.