Every building is unlocked in the HQ. Click on the HQ to view the base development tree and select the structure you'd like to build. If you have enough items, the 'Research' button will be available for you, click on it to start researching. (The necessary items can be produced in the Lab or purchased with war bonds.) You can also complete the research for war bonds instantly.
The Harvester Complex produces crystals, that are automatically converted into coins. You can upgrade the Harvester to unlock new contracts that allow you to produce more and more crystals.
It is built at the Underwater Crystal Field using the Contracts — items that are dropped randomly in PVP. After finishing its construction, the Underwater Harvester brings you a certain amount of coins every 15 minutes for a limited period of time (8 to 12 hours).
Produces oil. Can be upgraded to unlock new contracts.
Produces iron. Can be upgraded like the Oil Well.
Increases the troops limit at your base. Has six levels, each of them can hold 12, 18, 24, 30, 36 and 42 troops.
Gives additional troops limit increase.
The Depot stores resources (oil and iron). Can be upgraded to level 6 to hold 200 and 24, 400 and 48, 800 and 96, 1600 and 192, 3200 and 384, 6400 and 768 oil and iron at each level.
An additional Depot. Its six levels can store 3000 and 30, 3200 and 54, 3600 and 102, 4400 and 198, 6000 and 390, 9200 and 774 oil and iron.
Every unit lost in a battle turn up in the Hospital. As soon as you come back from the combat, the countdown starts. When it ends, ALL unhealed units and vehicles will be lost FOREVER. To start restoring a unit, select it in the list and click "Heal".
Restoring the units take a certain amount of coins. Units that were bought in the Shop or obtained as a prize in the Leaderboards can be ONLY restored with war bonds.
Units are healed one by one! If you've lost more than one unit, the "Heal" button will start a restoring process only for the selected one. If no units were selected, the "Heal" button will restore the first unit in the list, while others will wait their turn. If you have lost many units, you can instant-heal them all or accelerate the process of restoring particular units with war bonds.
Produces items required for the basic upgrades and creating other, more complex items. Has 3 levels, each of them unlocks new items, which are: Chemical, Ferrite, Elirium, Cryo Alloy, Energon and Ethernium.
Produces items for the high-end troops upgrades: Fuel Mix, Super Alloy, Killer Missile, Armor Plate, Turbine and Gun.
Here you can unlock new units (except for the naval ones).
Here you can upgrade all your units (except for the naval ones).
Naval Research Facility
Unlocks new naval units that can be created at the Shipyard.
Here you can upgrade your naval units.
Here you can create naval units.
MG Nests and Turrets can be placed on your base for protection. They do not affect troops limit.
Chain-link Fence/Razor Wire/Border Buoys
You can use them to fence off your base. Units cannot go through the Chain-link Fence, Razor Wire or Border Buoys as they must be destroyed first.
Decoration cannot be destroyed in a battle, but units can move freely through it.