Wind Waker: The black spot.
Moblin's Letter: Moe the Moblin is so moved by Maggie’s letter that he sends a heartfelt reply that cannot be delivered due to Maggie’s father’s prejudice. Link must deliver the letter directly to Maggie who reads the letter as a heartfelt marriage proposal and thanks Link by giving him a piece of heart. There may be a reading of the letter where Moe literally wants to eat Maggie, rather than figuratively wanting to eat her, but that is lost on Maggie.
Being given the spot is being given a warning, surrender yourself to the will of the crew or see your blood spilled. Some deposed captains are held in the brig to be turned ashore at the next civilized port of call, others are left marooned on a deserted island, and the unluckiest are put adrift in the open sea with a jug of water and a pistol with one shot. Only the bravest, slyest. or the most foolish captains ever try to resist the inevitable fall signaled by the delivery of the dread black spot.
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Based on my reading Robert Louis Stevenson created the idea of the black spot, and other classic pirate tropes, entirely for his novel Treasure Island. Makes you question how you know what you think you know.
Be excellent to everyone.
-Ceph