Sonic's Leather Costume
To unlock Sonic's leather suit, get the Sonic The Hedgehog, Sonic The Hedgehog 2, and Sonic The Hedgehog 3 cards. To unlock the gloves, get the Cream The Rabbit, Cheese, and Cream and Cheese cards. To unlock the shoes, get the Sonic and Amy, Amy Rose 2004, and Amy Rose 2005 cards.
Successfully complete Story mode with Shadow.
Successfully complete Story mode with Silver.
Successfully complete Story mode with Sonic.
Successfully complete the game with Sonic, Knuckles, Silver, and Shadow to unlock Metal Sonic. Alternately, collect the "Metal Madness", "Metal Overlord", and "Neo Metal Sonic" cards.
Knuckles' Leather Shoes
To get Knuckles' leather shoes, get the Buzzer 2002, Coconut 2002, and Turtloids 2002 cards.
Silver's Leather Shoes
To get Silver's leather shoes, get the Chaos 2 (1998), Chaos 4 (1998), and Chaos 6 (1998) cards.
Sonic's Ice Suit
To get Sonic's ice suit, get the Miles "Tails" Power 2002, 2004, and 2005 cards.
Successfully complete Story mode with Knuckles.
Metal Sonic Skin
Successfully complete Story mode with Metal Sonic.