Here is a set of Sonic X themed cards in a nice cardboard /plastic case. These are said to be rare. Are they regular playing cards? They're not trading...but they might be for a certain type of cardgame only. (like how Uno cards are) You might be able to figure it out if you could read the box, but it's in Hebrew.

A translation: "Card Game: War with Sonic & His Gang(Friends)" So, maybe some kind of battle cards or cards set up specifically for 1 game type. Translation provided by: That title likely says what the cards do.