Which 2023 Sonic game returned to 2D side-scrolling gameplay with local co-op?

Which 2023 Sonic game returned to 2D side-scrolling gameplay with local co-op? Sonic Superstars.

Released on October 17, 2023, Sonic Superstars is a side-scrolling platform game designed to evoke the classic Sega Genesis-era Sonic formula. Its levels use a 2.5D presentation, combining traditional lateral movement with modern 3D visuals and effects.

The game supports local cooperative play for up to four people. Sonic, Tails, Knuckles, and Amy Rose are playable, and each has distinct abilities: Tails flies, Knuckles glides and climbs, while Amy uses a hammer and double jump. Trip becomes playable after completing the main campaign.

A common mix-up is Sonic Origins, which is a compilation of older games rather than a new 2023 adventure. Sonic Superstars is also separate from Sonic Frontiers, the primarily 3D open-zone game released in 2022. Superstars was developed by Arzest and Sonic Team, with contributions from Sonic co-creator Naoto Ohshima.