Quote Originally Posted by davepesc View Post
And, as I understood it, you didn't get a complete game in card packs. You had to buy multiple packs in hopes of getting the card you want, like with baseball cards. This may be false, but the commonly-held perception (at least among those I knew) couldn't have helped.
In the case of the NES games, you got all the cards you needed in the pack; they weren't separated out into random booster packs. Just before it died in the US, there were plans to release a Game & Watch series, which would consist of randomly selected cards in booster packs, though I kinda doubt games of that size would have required more than one card.

Mainly, it was a number of problems; since the e-Reader had no save memory, you had to swipe a bunch of cards each time you wanted to play a game, which could quickly become tedious; the e-Reader could be rather touchy and require you to swipe a card multiple times before it would read it; and in the case of games like Super Mario Advance 4: Super Mario Bros. 3 (God, that's a long title), you had to have two GBAs, one with the Mario cart and the other with the e-Reader inserted, as well as a link cable, in order to scan in level and item data.

It was a great idea, and in the days before the rise of DLC, an ingenious way of downloading new content into games, but sadly it just wasn't executed too well. I believe it lasted quite a bit longer in Japan compared to the states... I'm pretty sure both Pokemon Colluseum as well as Pokemon Emerald accepted e-Reader cards to obtain new items and trainer battles.