You control a little icon of some kind (in the first level, a wireframe pyramid thing -- it changes with the theme every level) who shoots fireworks at stuff flying around on the top screen. You have to drag the little avatar around with the stylus, and then also swipe upward to shoot fireworks. If you hit the enemy, it blows up; if you miss, your shot explodes into fireworks, whose sparks then fall down towards the bottom screen and must be avoided. You can aim your shots by drawing lines at different angles, and you can shoot about as fast as you can slash the screen.
Gallery: Big Bang Mini
When you destroy an enemy, it drops a star that you have to pick up with your avatar. Once you've picked up enough stars to fill up a meter, you finish the level. After ten levels, you face a boss -- basically a big enemy that you have to shoot a bunch of times.
Each world, which has a totally different visual theme, features ten levels, and there are ten worlds. I played maybe three or four levels in my short time with the game, and found even the first one kind of hard. It's challenging to pay attention to your little avatar on the bottom screen while also aiming your shots at the top screen. Oddly, your avatar has nothing to do with the shooting: shots come straight from the stylus motions independent of the avatar's position. It's a neat DS-style twist on the static-screen (Space Invaders) shooter, with the wildly divergent visual styles Arkedo displayed in their last DS game, Nervous Brickdown. The graphical polish and the fast action make this totally one to look forward to when it comes out in January.
Oh, did I mention it's got an alarm clock mode? Because it does. An alarm clock. I didn't see it, but I saw the menu option