These cards have what are called situational abilities - they are really only good used in very specific situations. Most of them are played either right before or right after you roll. The abilities are very different from each other, everything from card that makes your opponent move his Bakugan around to one that lets you take back an Ability card you have already used. All of these cards will likely prove usable at some point in a game, so it's hard to make a mistake as a beginning player when you pick your card, so if you're just starting, pick the one that looks the most fun!