Refinery

Etherium refineries, or just refineries, are large structures that pump etherium ore from deposits in the ground. That etherium is then processed and refined into etherwatts, a potent energy source which is highly desired across the galaxy. Refineries can only be built on deposits of etherium. At least one unit must stand in the radius of an etherium deposit for 5 seconds to build a refinery.

Etherium deposits are sometimes occupied by enemies, who have their own bases situated on top. These must be destroyed before a refinery can be built. Towers can only be built near refineries, as they supply energy to the towers. If a refinery is destroyed, all associated towers are also destroyed. Thus, defending a refinery from enemy attacks is crucial.

Building refineries is the primary way to progress through the game. Without them, units cannot be recruited, and towers cannot be built. The planet Sagan-1 has many mining colonies because of the vast amount of etherium it contains. The planet is under the jurisdiction of the Federation, which highly desires etherwatts because of the amount of energy they contain.

Trivia

 * Etherium does not seem to be based off of any existing element in real life. However, the prefix "ether" refers to an organic compound that is part of the chemical makeup of many industrial liquids.
 * Despite never being explained in depth, etherium is highly sought after all across the galaxy. It is unknown where else it may be found, or what its other uses may be.