Sea Forts

Sea of Thieves

Sea Forts Guide

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The next step of Flameheart’s wicked plan is complete. He has successfully summoned six haunted Sea Forts from the Sea of the Damned to the Sea of Thieves. These Sea Forts are no longer just ghostly memories fading in and out of reality. Instead, they are now physical fortifications, fiercely defended by a crew of Phantoms loyal to Flameheart.

If you approach these Sea Forts, prepare for a barrage of cannonballs to rain down on your ship. If you survive the cannon fire and make landfall, you’ll then have to deal with dozens of fearsome Phantoms as you explore the Sea Fort.

Once you have conquered waves of Phantoms and defeated the mighty Captain of the Fortress, you will have cleared the fort and gained access to its treasury!

What is a Sea Fort?

Sea Forts are naval strongholds provisioned with cannons, resources, and treasure. Sea Forts were once ghostly memories drifting through the Sea of the Damned. Now, Sea Forts are physical fortifications that have materialized in the Sea of Thieves, waiting to be defeated and explored.

Sea Forts can be active or inactive. When active, Sea Forts provide a small raid experience for all pirates to try and complete. Unlike Skeleton Forts, Sea Forts do not have a giant cloud above them when active. Also, more than one Sea Fort can be active simultaneously.

An active Sea Fort will have raised flags that you can spot from a distance. At night, active Sea Forts will also emit a ghostly green light. As you approach an active Sea Fort, you will hear a warning bell toll as hostile Phantoms take up position to fire cannonballs at your ship. Once you are on an active Sea Fort, you will find weapon-wielding Phantoms roaming its halls, ready for a fight!

After clearing a Sea Fort, it will become inactive and undefended for a short time. While uninhabited by Phantoms, you can use the fort as you see fit. For example, you can use the kitchen for cooking some food, take a nap in any one of the many beds, or even defend your freshly earned treasure from incoming enemy crews!

Sea Fort

Where are Sea Forts located?

There are a total of six Sea Forts in the Sea of Thieves. You can find two in each of the three original regions. Each Sea Fort has a different look depending on its region.

The Sea Forts in The Wilds look like a gloomy prison with chains and cages scattered across them. In contrast, the Sea Forts in The Ancient Isles look like an overgrown ancient structure with lush plants sprawled all over them. And finally, the Sea Forts in The Shores of Plenty are very clean looking without any blemishes.

You can easily find one by scanning your Map Table on your ship. Just look for an island with “Fortress” in its name.

The six different Sea Forts are:

  • Imperial Crown Fortress
  • Royal Crest Fortress
  • Ancient Gold Fortress
  • Old Brinestone Fortress
  • Mercy’s End Fortress
  • Traitor’s Fate Fortress
Sea Fort

How to complete a Sea Fort

To complete a Sea Fort, you will first need to defeat seven waves of Phantoms. You will hear the ringing of a bell at the end of each wave, letting you know you’ve completed it.

Once you have finished seven waves, you’ll then have to take down a Captain of the Fortress during the eighth and final wave! The Captain of the Fortress is the fort’s last defense and will put up a good fight!

The Sea Fort is packed with resources and Ammo Crates to help you during battle. We managed to complete a Sea Fort with a Cutlass and Blunderbuss equipped. Also, be on the lookout for Ammo Pouches that Phantoms drop when killed! The extra ammo will be handy to complete the Sea Fort quickly.

Upon clearing a Sea Fort, the fort will no longer repopulate with Phantoms until you leave. But, until you do, you can take your time moving treasure to your ship and exploring every nook and cranny inside!

Captain of the Fortress

How to open the Fortress Treasury Door

Upon defeat, the Captain of the Fortress will drop a Fortress Treasury Key. You can use this key to open the door to the Fortress Treasury. Inside the treasury, you’ll find Gold Piles and lots of treasure for you to ferry back to your ship.

If you’ve lost the key during the heat of battle, look for a glint on the floor. The Fortress Treasury Key glints like treasure does from a distance.

Fortress Treasury Key

How long does it take to complete a Sea Fort?

The Sea Fort’s difficulty is based on the size of the crew who started the encounter. Depending on the crew size, it should take 10 to 15 minutes to complete a Sea Fort and retrieve the key to the treasury. You can expect to battle more challenging Phantoms if you have a larger crew.

How much gold does a Sea Fort give you?

Inside the Sea Fort’s Treasury, you will find Gold Piles and around 12k worth of gold.

You can also find dozens of Gold Pouches and other pieces of treasure hidden in cabinets, cupboards, and crates around the Sea Fort. If you have a keen eye, you could earn yourself an extra 2k worth of gold!

Another reason to scour the Sea Fort is to find the hidden Fortress Store Room Key! This key will give you access to the Storage Room on top of the Sea Fort with even more treasure inside!

Sea Fort Treasury

How long does it take for a Sea Fort to reset?

A completed Sea Fort will be inactive for around 12 to 15 minutes as long as no one is within 1km of it.

After you have cleared a Sea Fort, it will stay inactive for as long as any pirate is within 1km of it. Once everyone has left the Sea Fort and is more than 1km away, a 12 to 15-minute reset timer will start.

Anyone returning to the Sea Fort during the cooldown period will pause the timer.

How to unlock the Fortress Store Room

To unlock the Fortress Store Room, you’ll need to find the Fortress Store Room Key. The Fortress Store Room Key is hidden somewhere in the Sea Fort. Specifically, you can find it in any of the many cupboards, drawers, or crates scattered around the Sea Fort.

The Fortress Store Room Key is guaranteed to spawn, so if you can’t find it at first, keep looking!

Fortress Store Room Key

Where is the Prison Cell Key?

It’s not possible to open the Prison Cell at the moment. The only way into the cell is through the locked door, which requires the Prison Cell Key. Since no one has discovered the Prison Cell Key yet, we believe it’s not in the game to find.

Prison Cell Key needed

Commendations

Repeat Offender (1-5) – Opened Sea Fort Treasuries

Scoping the Joints – Visit all Sea Forts across the Sea of Thieves

From Whence They Came – Defeat Sea Fort Phantoms

Master Burglar – Discover secret stashed treasures on a Sea Fort

Spectral Slayer – Defeat a Sea Fort Phantom Captain

What’s Yours is Mine – Open a Sea Fort Treasury

Light Fingered – Discover secret stashed treasure on a Sea Fort

Faster Chef – Use all Sea Fort pans to cook food for your crew

Fort-y Winks – Share a bunk bed with another pirate

Get Off My Lawn! – Hit another crew’s ship with a Sea Fort Cannon

To the Tavern!

Aye, we pirates do love a good tavern. ‘Tis a place to share our findings and adventures. ‘Tis a place to clap each other on the back. ‘Tis a place to glean further insight.

Happily, we’ve found proverbial taverns on several social outposts—each bustling with a vibrant pirate community! Want to join in the merriment? Ye will always find a hearty welcome at our table!

Share yer Findings

Follow Along

To the Tavern!

Aye, we pirates do love a good tavern. ‘Tis a place to share our findings and adventures. ‘Tis a place to clap each other on the back. ‘Tis a place to glean further insight.

Happily, we’ve found proverbial taverns on several social outposts—each bustling with a vibrant pirate community! Want to join in the merriment? Ye will always find a hearty welcome at our table!

Share your Findings

Follow Along

Want to keep a weather eye out?

Jot down yer email, and we’ll be sure to let ye know when there’s something new on the horizon.

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