In this fun biology game, you play a vaccine that is trying to get stronger and stronger. To do this, you need to eat as many bad cells as possible. But if you try to eat them when they're big, they will destroy you. To shoot an enemy and get it small enough to eat, fly up by at and push the D button to shoot. Once an enemy is small enough to eat, it will have a glowing outline around it. To eat an enemy, get close and push the S button. The more that the upper right toolbar fills up, the more enemies you have eaten and the bigger you will get. This also recharges your weapons.