When longtime Sega mascot Sonic the Hedgehog made his debut on the Dreamcast console in Sonic Adventure, gamers were stunned. Sega had not only used the game to show off the tremendous possibilities of the then-new hardware, but they had reinvigorated the platform-style arcade adventure genre with massive, intricate levels, gleefully distracting minigames, and even a new kind of virtual pet, called a Chao, that could be combined with other pets, traded with friends, and even exchanged over the Internet. Sonic Adventure 2 ups the ante of its predecessor with all-new puzzles and levels, and even faster action reminiscent of the early Genesis-era games. Knuckles and Tails are back, as are the Chao pets (who can now talk!).