They are game cards, but the game aspect is very minor (small Speed and Skill numbers on the backs). They don't seem to follow the traditional "common-uncommon-rare" game card standard. It's actually a pretty nice set - clear plastic cards with rounded corners. The set includes 110 basic cards and 20 foil cards (the packaging calls them "holographic cards", but they're just foils). There are no stated odds for the foils. It just says "randomly inserted", but I got 1 in both packs I bought.

And I got one in each of the 24 packs I bought. I think the insertion wasn't totally random.

Yes it is a pretty nice little set, but a box gives 24 packs with 4 each of the "base" clear cards, which means you're frustratingly short of being able to hope for a set from one box, and two boxes gives you mucho extras without a guarantee that you'll finish a single set.

Here's a scan to give you an idea, for a few of the regular cards. The top portions (background) are the clear part, with transparent red and yellow checkerboard squares; the bottom third and the scene rising above the "horizon" are opaque. The holographic cards are more common individually than the less-special cards, so it's really a set of 130. Those cards are the same format as the clear cards except it's a metallic background instead of transparent.