Walls. With a wall in hand, click in line with your walls and the gap fills itself, up to 12 segments at once; or drag a line of its own. The wall stays in hand for the next run.
Power. The Fabricator Core and every Energy Core supply power; everything else draws it. When demand outruns supply, production and printing slow in proportion (down to 25%), Pulse Turrets fall silent, the radar goes dark and the Uplink goes offline.
Uplink. Once you have a Vehicle Factory you can print an Uplink. While it stands and the base has power, the whole map is in sight: the fog of war lifts, and every nest and creature shows. Lose it, or the power, and you see only what your units see again; the ground you saw meanwhile stays explored.
Repair and sell. Select a building to repair it (paid as it goes, W) or sell it (L, twice) for 50% of its worth, less for damage. Engineers repair buildings and vehicles for free.
Upgrades. Some buildings have upgrades: one level each, the Refinery three (more Sunresin a load, a second dock, its dock guns). Select the building once it stands and press R: it is paid at once, and the Fabricator Core’s drones fly out and print the new level, as fast as their numbers allow (slower on low power), while the building works on. It stays with the building; a sale returns only the building’s own worth.