Its story runs parallel to Sonic Generations (2011) and sees Shadow travel through time as he faces his former arch-nemesis Black Doom.

By defeating enemies, the player fills a meter that allows Shadow to activate "Chaos Control", which stops time, freezes objects, and allows access to alternate paths.

These unlock bonus content including concept art, summaries of Shadow's roles in previous Sonic games, and music tracks that can be played during stages.

Additional artwork and music can be unlocked by clearing challenges in White Space and finding parts for Orbot and Cubot's rocket.

[10] By purchasing additional downloadable content (DLC), players can equip an alternate skin for Shadow based on his prototype "Terios" design.

[15][16] An additional level, based on scenes from the 2024 film Sonic the Hedgehog 3, was released as DLC on December 12, 2024.

Shadow finds the fake Chaos Emerald previously created by Miles "Tails" Prower,[g] but he is caught in a time anomaly created by the Time Eater and pulled into the realm of White Space,[e] where a large object, the Black Moon, hovers.

As Shadow explores White Space, he discovers relics that cause his body to mutate and develop new powers.

Shadow encounters Maria and Gerald Robotnik, pulled from a time before their deaths, and wonders if he can avert their fates.

As Shadow returns to Gerald and Maria, the loss of Black Doom's power causes them to begin fading back to their time.

[6] They chose levels they found the most interesting and the most popular among fans,[3] while integrating Sonic Frontiers' open-world gameplay to add modern elements.

Senoue worked alongside a team of internal Sega staff including Kenichi Tokoi, Yuzuru Jinma and Hiro, and external contributors such as TeddyLoid, TORIENA, Audissi Studios, Circuit Freq, The Qemists and RichaadEB.

[35] Sega collaborated with Limited Run Games to produce a collector's edition including the soundtrack, an art book, a keychain with Sonic and Shadow's shoes, Chao figurines, a statue of Sonic and Shadow standing on a Dreamcast, a SteelBook case, and a mock Dreamcast jewel case.

[39] According to Metacritic, the Sonic X Shadow Generations bundle received "generally favorable" reviews from critics.