It's possible you're thinking of one of the following:
* The "Legacy" quest in Pirates of the Caribbean Online: This game featured a quest called "The Legacy of Captain Teague," which focused on finding Jack Sparrow's lost treasures. It involved solving riddles and uncovering clues throughout the game world.
* A specific riddle from a Pirates of the Caribbean movie: The films often featured riddles, but not necessarily a "Legacy Riddle" as a specific name. For instance, the first film featured riddles leading to the chest containing the Aztec gold.
* A fan-created riddle: There are many fan-created riddles and puzzles about the Pirates of the Caribbean universe. It's possible you encountered one of these.
To help me understand what you're looking for, could you provide some more context?
For example:
* Where did you see or hear about this riddle? (a website, a book, a game)
* What is the basic theme of the riddle? (Finding treasure, uncovering a secret, solving a mystery)
* Can you remember any specific words or phrases from the riddle?
The more information you give me, the better I can help you find the riddle you're looking for!