King Of The Castle Achievement

There are eleven forts to capture in the game, but only ten count for this achievement. On the map they will be red tower icons (green if you have already captured them). Generally, the further north and east you are, the easier the fort is to defeat. Upgrading the Jackdaw is essential to defeating them, especially your mortars. The forts will try to hit you with their mortars, so frequently changing direction is essential. Many of them will also have ships defending them, although that can be useful as you can cripple and board them and then use them to repair the Jackdaw mid-battle if needed.

Once the defenses of a fort are down, you will need to dock the Jackdaw and go ashore. There will be several officers to kill in the middle of a lot of regular soldiers. You can ignore the soldiers but will need to kill the officers and then go to a door and become anonymous to open it, at which point you can walk in and kill the commander (who just stands there and doesn't resist). At that point you will have visibility into a section of the map with all locations visible. You will also be able to repair the Jackdaw, recruit crewman, buy ammunition, and access a naval contract at the fort.

The forts are located at the positions below, along with the difficulty rating assigned by the developers:

• Fort Castillo de Jagua (356, 559) - medium
• Fort Charlotte (470, 272) - hard
• Fort Chinchorro (124, 357) - hard
• Fort Conttoyor (102, 547) - medium
• Fort Cabo de Cruz (566, 390) - medium
• Fort Dry Tortuga (254, 749) - easy
• Fort Eleuthera (726, 784) - easy
• Fort Gibara (657, 521) - easy ** This is a good choice for unlocking Owned if you have yet to do so as it only has two chests, two animus fragments, and one naval contract which is quite fast.
• Fort Navassa (728, 219) - medium
• Fort Serranilla (347, 140) - hard

The fort that does not count for this achievement is Fort Punta Guarico (776, 399), which is captured during Sequence 5, Memory 1: The Forts.