Could it be implemented in the game, few legendary items each with a mystical power.
To find these, there are no maps. Just tales. Hints released through different media.
(Bad)Eg:
Item - Lets say something like the cutlass with some simple power that doesn't affect pvp.
You don't get the whereabouts in a direct way. During exploration someone finds a scroll that says of the pirate. Mentions of the compass.
Maybe someone else later finds a drawing in a cave.
Google search of the name of the pirate reveals of a legend.
And this gets posted, and speculated upon social media, Reddit and definitely this very forum.
Maybe a new clue is released via a song sung in a pub.
At the end, clues lead from on to another and you finally find the treasure. Somewhere like a hidden cave which you have to enter from under water.
I think you might get my drift even with the bad example.
