No Escape

Ouch ! Your head hurts. The last thing you remember is that you've been knocked out. As you awake you are trapped on a grid. Monsters lurking around you, spawning from the middle of the screen. It seems that there is some kind of evil monster machine running - spitting out little bad guys.
Avoid being hit by the monsters and try to shoot as many as you can.
And ... to cut a long story short: Survive as long as you can !