how I beat it on hard..hehe. 1.) ramp up main gun but not all the way, then ramp up repair. Think lvl 7 you switch over to all lasers though main gun should be maxed (damage and rate) and repair should be maxed as well. Don't bother upgrading lasers too much and forget about lasers in the front.
Last level just before final boss sell everything and max out on # of planes. Then upgrade damage and rate. This leaves repair bots more time to focus on repairing your hull.
anyway I thought hard was impossible but this is how I did it.
final boss is not the frog but the King of Hell. Anyway, getting achievements after you beat the game is way lame. Why bother playing it again when it's easier.
Don't waste you time. The game is bugged at the end. You can't finish it, and it doesn't save after you beat the overlord. Also, the first one was better.
survival mode is just total luck on what spawns. if you get far then you got easy spawn lvls (ie. no 4 tanks+turrets). which is why golden commando doesn't help much.
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