Shadow Generations

Shadow Generations is a platform game that shifts between side-scrolling and 3D gameplay. Being included in Sonic X Shadow Generations, players can switch between Shadow Generations and the 2011 game Sonic Generations. As Shadow the Hedgehog, the player character of the single-player game, the player must complete a series of levels and bosses to defeat the alien warlord Black Doom.

Similar to Modern Sonic in Sonic Generations, Shadow can boost for extra speed, home in on enemies to attack, and stomp downwards to smash through obstacles and enemies. Unlike Sonic, Shadow can obtain power-ups granting him new abilities. 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. As the player progresses, they unlock transformations enabling new methods of attack and traversal. These include attacking multiple enemies with light constructed spears, surfing on water, launching larger enemies to teleport long distances, morphing into an alien to traverse certain terrain, and gliding through the air.

While Rouge the Bat and others attend Sonic the Hedgehog's birthday party, Shadow the Hedgehog travels to the derelict Space Colony ARK to investigate a report of strange activity. He discovers Black Doom, the leader of the Black Arms alien race and one of Shadow's creators, survived his defeat and pursues him. Shadow finds the fake Chaos Emerald previously created by Miles "Tails" Prower, but he is caught in a time anomaly created by the Time Eater and pulled into the realm of White Space, where Black Doom's base, the Black Moon, hovers. As Shadow explores White Space, he discovers relics that cause his body to mutate and develop new powers.

Black Doom plans to use the time anomaly's power to revive his forces and conquer the world, warning Shadow that the two will battle once his powers fully awaken. Shadow encounters Maria and Gerald Robotnik, pulled from a time before their deaths, and wonders if he can avert their fates.

Shadow Generations is part of "Fearless: Year of Shadow", a 2024 Sonic the Hedgehog marketing campaign centering around Shadow the Hedgehog to commemorate both the release of the game and of the film Sonic the Hedgehog 3, in which Shadow is prominently featured. Katsuyuki Shigihara, one of Sonic Generations' designers, directed Shadow Generations; other Sonic Team members who worked on Generations contributed. Sonic series producer Takashi Iizuka said that, as in Sonic Generations, Sonic Team chose to revisit levels from past Sonic games to recall Shadow's history. They chose levels they found the most interesting and the most popular among fans, while integrating Sonic Frontiers' open-world gameplay to add modern elements.

Jun Senoue served as the sound director for Shadow Generations, having previously done so for the original Sonic Generations. 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. Additionally, bands in which Senoue is a member—Sonic Adventure Music Experience and Crush 40—contributed to the musical score.

According to Metacritic, the Sonic X Shadow Generations bundle received "generally favorable" reviews from critics. According to OpenCritic, 82% of critics recommended it. IGN wrote that "This bulked-up remaster soars far and above previous enhanced versions we've gotten in the Sonic franchise, and hopefully will be the gold standard Sega holds itself to when it decides to bring back other Sonic games from the past."

The game also received praise from fans, and was nominated for the first round of the Players' Voice award at The Game Awards 2024.