Special buildings can be constructed in the large building slots. Some buildings are unique, whilst others can be constructed several times. Each building has a corresponding role: recruiting units, researching technologies, interacting with alliances and so on.
There's a total of 13 large building slots available, and 6 of the Special buildings are unique: Embassy, University, Warehouse, Tavern, Forge and Headquarters.
Embassy provides you with the means to interact with alliances: request troops, resources, find menus and tools that can be accessed either by tapping on the Embassy, or navigating to the Alliance button in the bottom.
Upgrading the Embassy increases the amount of resources and the maximum weight of units that can be requested.
When resources are requested, a message will appear in the alliance chat for other members to donate. A player can fulfill a request partially or fully by selecting the amount of resources to send. Each transaction is taxed for a share of the resources sent.
Resources are delivered instantly if both players are in the alliance's area of influence; otherwise they may take time to be delivered based on the distance between the two players' cities.
A request for units in the Embassy can be fulfilled in the very same way. These units will be housed in the Embassy and thus will not count towards the army capacity value of the city. Requested units can be used regularly as any other: they can be marched, stationed in camps, on the wall, in bastions and so on. However, when slain defending the city ("on the Wall"), they will not be available for healing in the Hospital.
You can construct two modules in the Embassy: Stables and the Customs Office. Stables increase the amount of resources that can be requested, and the Customs Office reduces the taxes paid when fulfilling requests.
University provides you with the means to research new technologies, critical to the growth of your city. You can only have one University in your city, but you can always employ an Additional Researcher to activate a secondary research queue.
Upgrading the University increases the speed of research conducted therein.
You can construct two modules in the University: the Cartographers' Guild and Scientific Workshop.
The Cartographers' Guild unlocks the "Marches" research tree, while the Scientific Workshop unlocks "Economy II".
Requirements: Stardust Mill
Warehouse provides you with the means to protect some of your resources when your city's defenders are defeated. Upgrading the Warehouse increases the amount of resources protected.
You can construct three modules in the Warehouse, all of which provide additional storage for each specific resource: Gold Cache, Stone Cache, and Wood Cache, respectively.
Requirements: Stone Quarry
Barracks allow you to recruit units. You can construct up to 3 Barracks in your city, and each provides a separate queue to recruit units. It's generally recommended to have at least two Barracks in your city, as you will be using and losing some of your units regularly, and it's important to keep resupplying your armies.
You can only recruit units available to you (Basic, Lesser Gods and Elder Gods units), though any units obtained from the Embassy, Spheres of Summoning, gifts and special offers will be viewable in your Barracks as well.
Upgrading the Barracks increases the size of the queue (how many units you can recruit at a time), while also decreasing recruitment time.
You can construct three modules in the Barracks, which further decrease the recruitment times and reduce the costs for specific unit classes: Shooting Range, Magic School and Training Grounds.
Required for: Wall, Hospital, Watchtower, Citadel
Tavern provides you with the means to view, recruit and equip generals. Some generals can be recruited with gold, whilst others may require crystals.
Tapping on a general displays their Star level, stats and abilities.
Upgrading the Tavern increases the amount of generals you can recruit (up to a maximum of 7) and marches you can have at a time.
Required for: Headquarters
Headquarters allow you to increase the unit capacity of your warlord (with stardust) and generals (with gold). Keep in mind that your warlord's / generals' capacity determines the amount (weight) of units they can bring with them (marching or into dungeons), and does NOT affect the capacity of your Wall. The Wall has its own capacity.
Upgrading the Headquarters allows you to upgrade your warlord's and generals' capacity values further.
You can construct the following two modules in the Headquarters:
- Training Camp that increases experience gained in PvP.
- Military Treasury that decreases the costs of upgrading your warlord and generals in the Headquarters.
Specific items may increase army capacity (such as the Battle Drum, Amulet of Expansion and Battle Horn), and the Quill of Accord reduces the upgrade costs in the Headquarters.
Forge provides you with the means to craft, enchant and enhance your equipment, manage your gems, as well as store and synthesize your materials and instruments. You can only have one Forge in your city, but you can always employ an Additional Blacksmith to activate a secondary Forge queue.
Upgrading the Forge increases your crafting speed, item storage capacity and unlocks new equipment for crafting. Keep in mind that your Forge level determines the items listed for requisitioning in your Port. As your Forge level grows, you will have to craft higher level items to fulfil the orders in your Port.
You can construct the following two modules in your Forge:
- The Aerial Lab that allows you to craft wings.
- The Jeweler's Workshop that allows you to interact with gems.
Workshop provides you with the means to build and repair traps. Each Workshop provides an extra trap building/repairing queue, while also increasing the total amount of traps your city can have. Keep in mind that some traps may require to be researched in the University.
Upgrading the Workshop increases its total trap capacity provided to the city, as well as the size of the queue, allowing more traps to be built at once.
You can construct the following two modules in your Workshop:
- Repair Bay that allows you to repair a share of traps destroyed by the enemies attacking the Wall. Repairing traps is usually considerably faster and less expensive than building new ones. You can additionally upgrade each Repair Bay to increase the capacity of the said Repair Bay (more traps available for repair). Any traps destroyed that exceed the capacity of your Repair Bay will not be available for repair, and will have to be built again.
- An Extra Workshop module that increases trap building speed.
Requirements: Lumber Mill
Hospital provides you with the means to heal the units slain when defending your city on the Wall. The Hospital becomes available at Citadel level 15, and you can build up to 3 Hospitals in your city.
Upgrading the Hospital increases the amount (weight) of units that can be healed when slain on the Wall. Units stationed at the Hospital do not count in the total capacity of your city. Generally, healing units is considerably faster and cheaper than recruiting new ones.
Keep in mind that units obtained as reinforcements from the Embassy cannot be healed, and will be lost if defeated.
You can construct the Pharmacy module in your Hospital, which reduces the costs to heal units (in gold).
Requirements: Wall, Barracks, House, Citadel level 15