Sleeper Hit
This game is a really well-done and deep CCG system.
It's only drawback is Intelligent Systems decided to wrap the gameplay in a very kiddie-friendly "story" where a kid runs around learning about the game, meeting "rivals" and conquering opponents in order to win pokemon badges, oops, I mean some tournament.

The text dialogues that are used to move the narrative can be tedious, but if you can stand it, this CCG system is AWESOME.

The name of the game translates into "High Speed Card Battle" and that's what makes this system so great, it condenses card game strategy and gameplay down to very dense and immediate terms.

The basic format of the game allows 10 creature cards and only 4 "effect" cards, making a deck simply 14 cards. A game takes less than five minute and a best 2 out of 3 match merely 15 minutes tops.

I am a long time MTG player and I've had my runs with other CCGs like Legend of the Five Rings, and even Pokemon. I recommend this game because it feels like the creature combat of Magic, minus all the convoluted abilities and minus the summoning sickness. You just take turns bashing each other, but the "way" you do makes a gigantic difference on the outcome of the game.

The game also reminds me of Magic without lands, minus the worry of mana screw and such. There is only one type of "power" or "resource" in the game, and it is controlled by one thing and one thing only, HOW MUCH YOU ARE WINNING/LOSING. If you are on the receiving end of a merciless beatdown, your resources expend and bloat, allowing you to play expensive and more powerful cards. But if you are dishing out the beatdown, you can only play cheap effects. It's a great central balancing mechanic and it makes the game feel tense and unpredictable even when you are winning.

Famitsu (Top Japanese gaming mag) gave this game
9/9/9/9

It even has WIFI play.