Please make sure you have checked the Players Guide thread first, before asking any questions.

Re: using the moon...

#2
You can build on a moon after constructing a lunar base. Moons start with one usable field, so if you build anything other than a lunar base, you won't be able to build anything else. So, Lunar Base -> other structures, always leaving 1 field remaining for the next level of lunar base.

It is possible to build robot facilities and shipyards on a moon, thus constructing ships and defenses.

Since moons do not produce resources, you can store resources on them, though it is not a good idea to simply leave them there unprotected. This will allow the planet to keep producing resources.

Moons also serve as the construction area for the awesome Jump Gate, which will allow you to move a fleet from one JG-equipped moon to another JG-equipped moon (meaning you need two) instantaneously, regardless of distance. You cannot move resources, but it's a way to take the largest of fleets across the entire universe in an eyeblink.

Moons furthermore can act as platforms for a phalanx array, which will allow you to check planets in range and see fleet activity to or from that planet - so if another player has a fleet deploying to that planet, you can see it coming and know when it will arrive.

Moons are also, themselves, immune to phalanxes - you cannot see traffic coming to or departing from a moon - if you phalanx a planet that is receiving a fleet from a moon, or deploying a fleet to a moon, you will see THAT, but phalanxing the moon will get you nothing.

Yes, they are extremely useful.
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