Great game, even If I must agree with grendels comments. And one more thing: In the old "Defender" the units changed there clothing as they leveled up, why is this not part of this game?
This game is really cool, but as always said: Needs a pause function and better upgrades, can't wait for a better version.
And a badge is more than needed!
 "Snail"){kind=icon}
 "Crunchball 3000"){kind=icon}
 "- Music in Motion -"){kind=icon}
 "Invasion3"){kind=icon}
 "Castle Crashing \"The Beard\""){kind=icon}
 "Protector"){kind=icon}
 "Momentum Missile Mayhem"){kind=icon}