Simply amazing.
First off, this game has a (minor) eduacational purpose. But it is very addictive. I love games where you collect money/credits to upgrade your vehicle/weapons. This game is perfect. It gos from insanely easy to insanely hard... I was I think on lvl 7 I had all the upgrades (basic shield upgrades, all lazers (hor. vert), sentinal shield upgrades.. But none of it helped on lvl 7... they have like 15 guys playing at you and theres those bloody red things that like chase you. But either way this game is EXTREMELY fun, im telling all my friends after writing this.