Once you’ve upgraded your Radar and started exploring new areas in the archipelago, you’ll come across some Resource Bases. In order to receive the resources these outposts produce, you must first conquer them. But beware! Other players are interested in the resource as well and might try to take the Base from you. The fight over a Resource Base can go back and forth for quite a while.
Every time one of these islands changes owners, its buildings are upgraded and/or new defensive buildings are built automatically (you cannot make changes yourself). Note that sometimes not all the buildings might get upgraded at once because if that would happen, the difficulty of the Resource Base would increase too fast.
Also notethat the production rate of the Resource base will always remain the same.
After a few days of fighting, you’ll be given the “Find a new opponent” option which allows you to find a new Resource Base with a different opponent.