Territory and trade
Claiming land, and trading goods, power and rides with other players.
Watchtower Claims the land around it while its brazier burns, so other players can't build there. Reaches further from high ground. Sends an automation signal while enemy troops are on its land. 
Power Exchange Sells power from one district's network to the district across the border. 
Trading Post Trades goods with the district across the border at a fixed rate. 
Toll Tube Station Lets your beavers ride another district's tubeway for a toll. 
Toll Station Lets your beavers ride another district's ziplines for a toll. 
Troops Counter Counts your troops that are ready, in training, deployed, fighting or wounded. In district mode, it counts the troops of the district's barracks and ranges, wherever they are.