Sonic Adventure 2is a 2001 platform game developed by Sonic Team USA and published by Sega for the Dreamcast. It features two good-vs-evil stories: Sonic the Hedgehog, Miles "Tails" Prower, and Knuckles the Echidna attempt to save the world, while Shadow the Hedgehog, Doctor Eggman, and Rouge the Bat attempt to conquer it. The stories are divided into three gameplay styles: fast-paced platforming for Sonic and Shadow, third-person shooting for Tails and Eggman, and exploration-based treasure hunting for Knuckles and Rouge. Like previous Sonic the Hedgehog games, the player completes levels while collecting rings and defeating enemies. Outside the main gameplay, they can interact with Chao, a virtual pet, and compete in multiplayer battles.

Tagline Sonic Adventure (ソニックアドベンチャー Sonikku Adobenchā?) is a 1998 video game developed by Sonic Team and published by Sega. It was released on the Dreamcast, marking the first Sonic the Hedgehog title on a sixth-generation console.[1] The game marks the series' shift to 3D gameplay, introducing a redesigned, expanded cast and voice acting. As the first mainline 3D game in the series, Adventure brings the 2D platforming mechanics of its predecessors into a three-dimensional world. The story revolves around six distinct characters, each with their unique style: Sonic, featuring traditional high-speed platforming; Tails, who introduces racing elements; Knuckles, focusing on treasure hunting; Amy, incorporating stealth-based missions; E-102 Gamma, offering a shoot 'em up experience; and Big, centered around fishing. The game's narrative revolves around Chaos, a deity of destruction unleashed by Doctor Eggman. Adventure began development in April 1997 under the working title "Project Sonic", initally slated for release for the Sega Saturn. However, as the Saturn's limitations became apparent, the project was moved to the Dreamcast, allowing the team to fully exploit the new console's potential. Sonic Team made efforts to adapt the classic Sonic characters to 3D, leading to a significant redesign of the cast to better fit the new style and improve their in-game visibility. The game's diverse environments, which ranged from ancient ruins to lush jungles, drew inspiration from the team's travels to the Americas. Initially released in late 1998 in Japan, an updated edition was later developed by Sonic Team USA and released worldwide in 1999, under the name of Sonic Adventure International (ソニックアドベンチャー インターナショナル Sonikku Adobenchā Intānashonaru?) in Japan. Being the first 3D Sonic game, Sonic Adventure was highly anticipated and received critical acclaim upon release. It was praised for its visuals, presentation, and gameplay,