A Card Game of "The Cool Blue Dude". The image on the front is Japanese. Does anyone have images of the cards themselves? The cards were quite high quality, similar to Pokemon cards, & are about 8 inches in length & 5 inches wide.
The default game is chancy & random, yet quite fast (typical basic childrens card game) & was for four players or less. However, due to the broadness of the card set, many different games can be played. It consisted of 7 "character" cards & many "ring" cards. The character cards had a Sonic character printed on it (Sonic, Tails, Princess Sally, Dr. Robotnik, Crabmeat, Caterkiller and Buzzbomber - Sonic, Tails, Sally and Robotnik were all "AoStH" style and the Badnik cards were in-game style) & the Ring cards had a number of rings on a basic Marble Zone background.

The aim of the basic game was to draw cards & "ring-out" as many characters as possible within the time limit. The player, on his turn, draws a card - if it is a Char. card, he/she must take it for themselves. If it is a Ring card, they put it in the "discard pile". If the player draws a Ring card with a one ring value, he/she attaches it to a Character card. Then it goes to two, then three, then four until eight. Once a character card has 8 ring cards on it, the player earns a point & the character & all rings cards are put on the discard pile. Once the deck is empty all cards in the discard pile are re-shuffled & the game is played over. Once the time limit runs out, the player with the most points wins.
Info by MetalMandible.