This game is one of the most unique concepts I've seen. It's a puzzle fighter, but has more elements of fighting games than most puzzle fighters.

Concept is really simple: Put similar colored blocks into groups of 3 or more to send them as projectiles to the opponent. If they get hit, their board shrinks. Repeat until one player loses.
Sounds simple right? Now add in 10 unique characters, each with their own passives and supers, a "hype" meter which acts kind of like an X-factor, and a parry mechanic and you have a deep and interesting game.

That said the game is not perfect, and does in fact have a few fatal flaws, most notably that there is no online mode. On top of that, the single player options are pretty limited. As fun as this game is, if you're not playing against other human beings, this won't have long lasting appeal to you. I have heard that it works over parsec, but I admit I haven't tried this myself since I have a local scene who plays, and we've even done quite a few tournaments for the game.
Unfortunately, the updates to the game are also irregular, which also doesn't help with the lasting appeal.

Still, I strongly suggest that you try it out since it costs less than a Happy Meal, and try to get your friends to play it for a really good time.