There are a total of 15 characters on the Team Sonic Racing rooster. Not all of these characters though are available from the start of the offline story-based single-player Team Adventure mode. At the start of this mode the only characters that are available are Sonic, Tails, and Knuckles. Also, in the first few races you will only be racing against Amy Rose, the Chao, and Big the Cat. This 'How to Unlock Characters' Guide will tell you how you can access the rest of the characters.
To unlock the complete roster of characters in Team Adventure mode you simply need to keep playing through the story. As you pass into new Zones you will unlock a new team of characters to race against. These new teams will join those already unlocked, making the game more difficult as you progress. The hardest team to get because the characters are unlocked in the later stages of the game is the villain team which consists of Dr Eggmn, Metal Sonic, and Zavok.
Check out our Choosing a Racer Guide to make sure you pick the right character for your play style.
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