It’s nice to have your ship as your home in Sea of Thieves, but the game gives you the option of taking some stationary Sea Forts to use as your base and place of rest. There are six Sea Forts around the Sea of Thieves, and you can capture them fairly easily with just your fellow crewmates without an alliance. More than likely, you can take them on all by your lonesome. Be prepared to spend about 10 to 15 minutes to claim a Sea Fort, and be sure to stock up on fruit beforehand – it’ll be a lot of swashbuckling action.
Sail to the fortress
We’re assuming that you’ll sail towards whichever Sea Fort is closest to whichever Outpost you spawned on. Figure out the location of the Sea Fort you want to take, mark it on your map, and set off in that direction. Like with Skeleton Fortresses and the like, you’ll know that a Fort is active when enemies are firing cannonballs in your direction as you get closer. At night, these forts will have an eerie green glow to them.
Park your ship and make your landing
You’ll want to place your ship near enough to the fort that it will be out of range of cannons, and should your pirate character perish, you’ll respawn fairly close if you’re in a good parking spot. You’ll want to search for any ladders that you can climb up.
Fight your way up
Immediately upon making landfall at the fort, enemy Phantoms will spawn in hordes and attack you relentlessly. They don’t put up too much of a fight — remember your standard combat strategies with Phantoms. These Sea Forts aren’t big enough to be considered labyrinths, so circle around to make sure you see any doorway and staircases you can go through; you’ll generally be moving upward, finding trapdoors, stairs, and ladders. Waves Phantoms will continue to spawn on you no matter where you go, signaled by an ominous bell. Pick up fruit from the numerous barrels you’ll pass by; you’ll need them to heal up.
Defeat the Captain
Several waves of Phantoms will attack, and the final wave will be marked by the arrival of the Captain of the Fortress. This Captain has several more Phantoms at its side, and while each individual Phantom is easy enough to dispatch of, things get hairy when you fight clusters of them. The Captain can’t really do anything special, but it can take a lot more hits than your usual ghosty.
Open the Fortress Treasury and loot away
Once you’ve defeated the Captain of the Fortress, the usual triumphant music cue will play, and the Captain will drop a Fortress Treasury Key. Pick it up and look for the Treasury on your now-claimed Fort; it should be to the left of the jail cell on the first floor. Open up the Treasury and make off with the loot.
You now have the space to freely explore the fort; you can open up a gate to let a rowboat inside and gather loot on it. A map table allows for group planning, you can sleep on beds to heal, and stoves allow you to cook pieces of meat. Check every nook and cranny for hidden trinkets of treasure; opening several containers, cabinets, and drawers will eventually earn you the Master Burglar commendation, and you should be able to find an additional Fortress Store Room Key in one of them. The Store Room is outside, on the top floor of the fort.
The fort is yours for as long as you occupy it; leaving it for some time will result in the fort expanding for the next crew to take.
