The game most notably introduced two major characters: Shadow the Hedgehog, a black hedgehog with upward-curled quills, amnesia problems, and a singular focus on finding out his reason for existence, and Rouge the Bat, a large-breasted treasure hunter who harbors a healthy obsession with jewels, both of whom appear in more subsequent games than any new character introduced afterward.
Sonic Adventure 2 was one of the final Dreamcast releases to come directly from Sega before the system was discontinued in 2001 the game was slightly tweaked and ported to the GameCube shortly afterward, sporting new battle modes and Game Boy Advance connectivity, and furthered the precedent set by Sonic Advance of Sonic the Hedgehog appearing for the first time on a Nintendo system.
