What if you had a chance to get "HIDEOUT KEYS" when you dig for treasures on X-marks and on riddles.
These keys would lead you to the hideout where an dead Sea Of Thieves pirate stored his fortune during his life on the sea.
This is how it could work:
You are your crew got lucky and dug up a "hideout key". You take a closer look at the key and see that their is an arrow on it pointing in a certain direction. You decide to follow the arrow and end up on one of the many islands on sea of thieves. You search the island and find a amount of "Ghost pirates" lurking around a door in a mountain wall. You notice that the keys arrow is pointing towards that door. you and your crew kill the ghost pirates and open the hideout and claim a big reward. You also get lore about the pirate captain that collected the loot that is now yours.
Different keys and hideouts can be implemented into the world. The ghost pirates spawns when the key is close to the island as they can sense that someone is after their treasure.
