Big the Cat

Big the Cat is a purple, tabby, dim-witted cat who first appeared in Sonic Adventure.

Sonic Adventure
Big debuted in this game as a playable character, where he would rescue Froggy.

Sonic Adventure 2
Big can make cameos in cutscenes and levels by repeatedly pressing the jump button.

Sonic Heroes
Big, along with Cream and Amy, are members of Team Rose.

Sonic X
???: He has a minor role.

Sonic and the Secret Rings
Cameos only.

Mario & Sonic series
Only appears in the first two installments.

Sonic Colors
Only appears in DS version.

Trivia

 * Big is the only Sonic Heroes playable NOT to return as a playable character in Shadow the Hedgehog.