There were actually four sets of Express Chess cards. Each package contained a number of cards with a picture and a chess symbol on it, and a few extra cards with special abilities. The four sets differed by the distribution of the pieces, the special abilities (unknown to me), and the themes: each set had a theme, and the cards had pictures from the themes. Two of the themes were African wildlife, and spacecraft.
I do not have the rules of the game. Some additional information and artwork can be found on the Boardgamegeek (search there for Express Chess) website.
If you have more information, or pictures that we can use here, please contact!