Amazing gameplay, strategy amazing, lots of fun, addictive, very few bad points.
You have to collect energy, that is key. You then set up a base. Some of the things you can set out are useless in some conditions, while others are useless because you can buy something better at the same price.
You have a main hub, and your base is connected to it like a spider. If the main hub is destroyed, you lose. If anything is destroyed, anything connected to it is also destroyed. The element of fun is that you have to time it right, as it shoots out your next expansion according to your aim, and it could go astray.
The only weakness in this game is that you shouldn't ally yourself with computers, as all they do is leech off of your defenses...