Sonic the Hedgehog Cards Title
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Individual / Misc. Sonic Trading Cards & Decks
The cards on this page don't belong to any particular game or set. They're promotional items, actual decks of playing cards or other card type accessory items. However, just because they're not a game or set, it doesn't mean you can't collect and trade them too!
Not right to fight foil card oddity "Cool Kids Know It's not right to fight" and "Keep your wits, choose to split" with "No one wins with violence".
Fighting card public announcement back For a community service card, this one is actually rather neat. The front is a shiny foil that shifts tones (sunset like). It doesn't really show well in the scan. The characters (poor Tails) are also foil tone.

This was a freebie included with some other item, but it is not known which. It is not a part of the above series, and it is not common.
Sonic Playing Cards Photo Well, can't forget playing-cards.
After all, they were the first type of cards. This seems like an ordinary deck (diamonds, clubs, spades, hearts etc) but the backs of each one have a Sonic theme. The pointing stock art is well colored, and placed over what looks like comic panels of a board game. However, no one knows if a board game of Sonic actually exists, or, if it does, why you would need an ordinary deck of playing cards to use it. The panels say things like "Go back 2 spaces" and other 'directions' with arrows.
Cookie Crisp Cereal Sonic Cards Holograms
Here are some cards from Cookie Crisp Cereal.
As you can see in the photos, the images are change-able, depending on the viewing angle. This is called lenticular, but no one ever remembers that. Each card has 3 images inside. The first one will show Tails standing and then running as an alternate image, and the second may be a spin-attacking Sonic and something else. (thanks to Juni for the changing info) The backs have profiles that are the same as the plush dolls from this era. The "Game Tips" are not actually tips at all, but rather descriptions of why Sonic 2 is so good.