As gh0un said before: on "harvest" missions, build only FEW miners. Mine SLOWLY. Right after each attack is started, you should STOP mining... This is stupid, but the game does NOT send enemy ships after given amount of time. Instead, the enemy starts attack after given amount of minerals is mined. This sucks a little :( However I found it at the end of my gameplay, so still enjoyed it ! ;)
The game UI sux itself:
1. I hate to wait and look a thousand times for the same zoom in -> zoom out -> zoom in (I want to shoot, not wait !) when ball is fired.
2. Hate to wait after last ball is fired, but the castle is not down. Then again - wait, wait, wait, instead of just clicking "retry".
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