What are Sea of Thieves’ skull clouds, and how they help you get the skeleton fort key

For Sea of Thieves players, a skull cloud appearing in the sky means one of two things. For the combat-averse, it means avoid the area, just totally steer clear. But for the more daring, gold-motivated pirates, a skull means it's time to fight for a massive bounty. Each skull cloud hangs over a fortress, which hosts the Sea of Thieves raids. Whether you're wondering how many rounds it takes to get to the boss or how to best fend off attacking players looking to cash in on your hard work, here's what you need to know about skull clouds, skeleton forts, and those precious fort keys.

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The Skull Cloud

Let’s get the obvious bit out of the way first: when you see the skull cloud, sail towards it. Underneath is a skeleton fort, manned by (surprise surprise) skeletons, who are in turn manning cannons. They’re very accurate, so make sure your best sailor is manning the steering wheel as you want to avoid as many of their cannon balls as possible. Don’t be scared if there are other players’ ship waiting when you cast anchor: you should all team up together to take on the waves of skeletons that will soon be inching your way. In fact, if the eyes are intermittently blinking red it means that another crew is currently battling through the fortress to get to the sweet loot inside, so you might want to give them a hand. 

Taking on the Skeleton Fort

When you land on the island, you’ll be met by a not-so-friendly horde of skeletons. Fight off the first wave with your friends (we really don’t recommend going in alone), then stock up on bananas and ammo before the next onslaught starts. You’ll know when the next wave is about to strike because a horn will be sounded when it’s near. 

There are around 10 to 20 waves of skeleton enemies, depending on the size of the fortress you’re attacking. And what makes it even more… fun… is that you’ll face different types of skeletons. The normal ones are white, with blue headbands on. But then there are green, leafy ones that regenerate health in the water. Grey ones that are weakened by the sunlight or the light from your lantern. And gold ones that can’t be attacked unless you douse them in water, or lure them into the shallows. 

Eventually a skeleton captain will turn up. Defeat it, and grab the skeleton fort key that it drops. It’s also known as a stronghold key, so don’t panic if it isn’t described in the same way. Now you can get into the Cursed Island treasure room. Plenty of skeletons will try and prevent your progress, so make sure you tackle it in a sizeable group so one of you can ferry the treasure back to your ship while someone else defends you. 

Oh, and other crews can and will steal your treasure if you give them the chance, even if you’ve killed all those skeletons yourself. So keep an eye out for those salty sea dogs. 

Zoe Delahunty-Light

While here at GamesRadar, Zoe was a features writer and video presenter for us. She's since flown the coop and gone on to work at Eurogamer where she's a video producer, and also runs her own Twitch and YouTube channels. She specialises in huge open-world games, true crime, and lore deep-dives. 

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