Sonic Superstars [Model HAC-A7YPA-JPN]

Released in October 17, 2023 in Japan.

The idea for Sonic Superstars originated with Sonic Mania (2017), a 2D game developed by Christian Whitehead, PagodaWest Games, and Headcannon. The Sonic series' producer, Sonic Team's Takashi Iizuka, was surprised by Mania's success and saw it as confirmation that fans were still interested in the series' "classic" style. Sonic Team and the Mania developers, who formed Evening Star Studio in 2018, began discussing another collaboration following Mania's release. They did not want to make a Mania sequel since Iizuka felt casual audiences would dismiss it as a rehash; he wanted to abandon Mania's pixel art style as Mania had been intended for hardcore Sonic fans, and he thought a new 2D game needed to appeal to a broad audience.

Whitehead said that Sonic Team and Evening Star "agreed early on that we should try to make something fresh", such as using a new art style like traditional animation or 2.5D graphics and not reusing content from prior Sonic games. Evening Star created a 2.5D prototype that experimented with depth using its in-development Star Engine. However, Sonic Team and Evening Star eventually decided against developing the prototype into a full product, and Evening Star moved on to develop Penny's Big Breakaway (2024). Whitehead denied rumors that the decision was caused by creative differences and said that Evening Star's relationship with Sega remained friendly.

During a COVID-19 pandemic lockdown, Iizuka and Sonic co-creator Naoto Ohshima held a drinking party over Zoom for fun. They expressed mutual interest in a new 2D Sonic game and began discussing a collaboration. Although Ohshima left Sega in 1999 and had not contributed to a Sonic game since Sonic Adventure (1998), he remained a fan and had enjoyed games such as Sonic Colors (2010), Sonic Generations (2011), Mania, and Sonic Frontiers (2022). Additionally, he noticed many of his followers on social media were Sonic fans and wanted to show his appreciation for them. Although Evening Star was no longer involved, many of the ideas Iizuka had discussed with Whitehead heavily influenced those he developed with Ohshima; Evening Star received a "special thanks" credit in Superstars.

Development on Superstars began in early 2021 and lasted two-and-a-half years. Ohshima's studio Arzest primarily handled development, with Sonic Team providing support. Shunsuke Kawaraduka directed Superstars, with Iizuka, Ohshima, and Yasuyuki Tsuzuki serving as producers. Iizuka felt Arzest was a natural fit due to their experience developing 2D games for Nintendo. He compared Ohshima's return to a family reunion and said that he had retained his design sensibilities from the Mega Drive era. Several Sonic Team members, including Iizuka, flew from Burbank, California to Yokohama, Japan to assist. The game was developed from scratch using the Unity game engine, though the physics code was translated from the Mania version of Whitehead's Retro Engine. The title, Sonic Superstars, reflected the game featuring the "superstar" Sonic characters.