A Castle is a very important building in the game. It is unique in that it makes the city upon which it is built vulnerable to attack by siege and plunder, and also doubles the army size of the city.
A Basilica at level 8 is required to build a Castle, as well as 20,000 Stone. Although not strictly required, it is best to wait until you get at least 3 cities and arm them well to build a Castle.
- Once a Castle is built, it cannot be cancelled from the Build Queue or demolished, so pick your time carefully. In this way it is similar to the Basilica: it can be downgraded to level 1, but not completely demolished.
- When a Castle is built or upgraded, it doubles the maximum army size of the city, so that you do not have to upgrade as many Barracks.
- A Castle allows a player to plunder, scout, siege and assault other players, but also makes it vulnerable to being assaulted and having all the troops killed, sieged and captured.
- The Castle is one of the most expensive buildings in the game, costing 20,000 Stone just to build it to level 1. If you want to upgrade a Castle, you should have plenty of Stone on hand.
Everyone builds their Castle in their own time. However, here are some strategies if you are not sure about when you should build yours:
- One popular strategy is wait until you have enough troops raiding that they fill up all the command slots.
- Another is to wait until everything is built up and troops are enlisted. For example, if a dedicated cavalry city is being built that can hold a maximum of 250,000 cavalry units, it is best to wait until that limit is reached.