Shadow was only intended for this one game, but with overwhelming popularity among fans, Sonic Team decided to bring him back for future games.
The last Sonic game to appear on a SEGA game console.
The Gamecube version of this game was the first Sonic game to appear on a Nintendo console.
The first Sonic game to introduced Shadow the Hedgehog and Rouge the Bat.
When Maria is preparing to launch Shadow from Ark in the English audio she says "Sayonara". In the Japanese audio she says "Adios".