Reactor

The Reactor is the core of the base and are needed for a base to function. Reactors also store and create Energy and Metal. Reactors also have a very large blast radius. It is said that this runs on moon stuff from one of the commanders.

Fortifying the Reactor
You should always try to fortify the reactor because it is needed for your survival. If you don't have a lot of buffer between your Reactor and the outside of your base, you should always try to use Metal.

Attacking the Reactor
Always try to use Cannons if you think you can't get the base with Lasers.If you can get enough Cannon hits close to the Reactor then the Reactor will inevitably explode. Although much of the Cannon damage can be countered by Sandbags, which are a cost-effective way of absorbing the energy of Cannons.