The Uncrowned Prince is a legendary rapier hidden inside an unmarked underwater chest in the Caribbean. You do not buy it, and no mission unlocks it. Instead, you sail to a specific stretch of coast, dive, and pull it out of a glowing chest resting on the sea floor. Because the location sits away from the usual routes, it is easy to sail right past without ever knowing it is there.
Quick answer: Sail to coordinates 500,167 in the region of Charlotte, west of Kingston. Anchor the Jackdaw, dive into the water, and loot the glowing white chest near the coral to claim the Uncrowned Prince rapier and the Guardian Beast figurehead.
Where the Uncrowned Prince rapier is located
The chest sits off the southern shore of Charlotte, in a small inlet on the main island that lies directly west of Kingston. The exact target is coordinates 500,167. If you have already synchronized with Kingston, fast travel there and sail west to reach the spot quickly.
Once you are close, place a custom marker on the map at the coordinates so it shows up on the compass at the top of your screen. That marker is the most reliable way to line yourself up, since the chest is unmarked and the surrounding water covers a lot of ground.
The chest was first found in a very specific pocket of the ocean, tucked against a cliff wall where two large pieces of rock jut out slightly over the water.
Prepare your oxygen before diving
The chest sits deep beneath the surface, so you need a way to stay underwater long enough to reach it. If you own the Diamond Trinket, equip it to extend how long you can breathe while submerged.
If you do not have that trinket, change a gameplay setting instead. Open the main menu, go to the Gameplay tab, scroll to the Playstyle section, and turn on the Unlimited Oxygen option. With that enabled, you can explore the sea floor without running out of air or losing health while you search.
Note: You do not need to worry about combat here. No sharks, urchins, or jellyfish patrol this spot, so you can focus entirely on finding the chest.
How to reach and loot the chest
How to equip the sword and figurehead
To use the sword, open your menu, select Inventory, and pick the rapiers. You can confirm the pickup worked once the Uncrowned Prince appears there as an available weapon.
If you prefer the look of the Uncrowned Prince on a different blade, choose the Customize option on your equipped sword and apply its appearance. The Guardian Beast figurehead can be attached to the Jackdaw from the Appearance tab, at any Harbourmaster, or from the ship’s Captain’s Quarters.
Uncrowned Prince stats and perk
The Uncrowned Prince is a Rapier-type legendary sword. Its Heavy Strike is a thrusting attack with long reach, which is standard for the rapier class. Its defining feature is a passive that restores health when you break an enemy’s defense.
| Property | Value |
|---|---|
| Rarity | Legendary |
| Sub-type | Rapier |
| Damage | 25 |
| Maximum Takedowns | 3 |
| Perk | Recovers some health after breaking an enemy’s defense |
Is the Uncrowned Prince worth using?
The 25 base damage is not remarkable for a legendary weapon, so on raw numbers alone the Uncrowned Prince lands only slightly above average for mid and late-game content. The value comes from its passive. When you fight several enemies at once, the health you gain from breaking defenses adds up and gives you steady sustain.
Its biggest advantage is timing. Because you can reach the chest without fighting anyone or advancing the story, this is a strong early-game pickup. The extra health makes boarding tougher ships like Man O’ Wars and taking control of forts far more forgiving for players who have not upgraded much yet. If you are just starting out, it is well worth diving for. If you already carry a higher-damage sword late in the campaign, the Uncrowned Prince becomes more of a situational option than a permanent upgrade.
