User blog comment:Ouroburos.TheNewSaurian/Sonic Adventure 3: New Information/@comment-3970002-20110507224247/@comment-3445303-20110507225404

If you weren't looking at the information above, then you will notice a game mode for SA3 known as "Sonic Evolution". That lets you play both Sonic Adventure and Sonic Adventure 2: Battle, along with other classic Sonic titles... Hope that helps!