Bonus Hints: Get 2 same color Perfect stones in one set and you get a Great Stone of that color. Get 4 Perfect stones in any color in one set and you get an Uber Stone (although it's extremely rare).
Like 22knight said, don't shoot the towers, just destroy those monsters as long as you can without destroying the towers. The best level for this is level 5. Destroy every tower except for the one that spawns those little shield monsters that stay close to their tower (It's on the left next to a base that produces those arrow looking things), just destroy every base except that, walk away or do something else for as long as you want (they don't attack), come back and destroy them all. Also don't upgrade to missiles if your going to do this as they sometimes destroy the towers.
You can beat the whole game with (1) Small Bubble (resize it to the smallest size) and as many missile launchers as you can fit (not the rocket launchers, use the launcher that fires one missile) also resized to the smallest size. Just fit them around your bubble and fly around blowing everything up without getting hit! And the best part is no long wait times to get from one end of a bubble to the other!
My current end-game ship:
Military K-2 Bullhorn XIII
7009T
12,708 HP
32,636 EU
Paid 68,000
Heavy Hyper Engine XIII
1193 Thrust
1631 T
(I go 17 m/s)
Paid 430,000
Weapons
3x Heavy Screamers XII/XIII's
Total 3,970 damage/s
Paid 98,000 for all 3
I can fire for quite a while before batteries give out. With weapons that don't use as much energy you can easily get stable.
Repair Droids
Dual Huge Repair Droids XII's
1,228 Repaired every 10 sec or 122.8 per second
Paid 1,400,000 and 1,700,000
Oh, and those stats are before skills :)
SHIP: Stick with Bullhorn through the game (at least for combat) it's easily the best ship. It has enough hold and integrity with insane amounts of battery so you can load on high damage weapons
WEAPONS: Screamers are probably the best combined with a Bullhorn, Blasters if you can't get high enough powered screamers. Missiles just plain suck.
ENGINE: Get the fastest you can, simple.
REPAIR DROID: Get the one with the highest repair amount, again simple.
Tactics: Accept as many "Eliminate Ship" missions as you can, fly to stations, get really close and fire
Really the only thing you should pay high prices for are the repair droids. Like other people have said, just because something is high priced doesn't mean it's better.
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