Drowned Man's Halo

Curse. The Drowned Man’s Halo is one of the thirteen unique Graven Rings. Like the others in the set, it bears a terrible curse.   This mooring ring is cursed. This fact is not revealed by the detect magic or identify spells. Attuning to the Drowned Man’s Halo curses you until special removal requirements are met. While cursed, the mooring ring cannot be unattuned.   When you cast a spell with concentration, you immediately begin to drown. You can survive without air for a number of rounds equal to your Constitution modifier (minimum of 1 round). After these rounds pass, at the start of your next turn, you drop to 0 hit points and are dying. You cannot regain hit points or be stabilized until you can breathe again.   Each time you succeed on a Constitution saving throw to maintain concentration while drowning, your remaining rounds of survival are reduced by 1. If your concentration ends for any reason, you begin breathing again at the end of your next turn.   While drowning you cannot speak or cast spells with verbal components. This curse has no effect on creatures that do not need to breathe.   Removal Requirements. The curse can only be lifted through drowning a living creature in the ocean. This ritual requires reducing the creature to 0 hit points, and while it remains alive but unconscious, remove curse must be cast upon you.   History. The Graven’s primary trade ship, the Dead Ringer, was lost at sea in 5,922 DA. I believe the usurping Gravens destroyed it on their passage to Kantier. The only known survivor was the First Mate, Santiago Crow, who washed ashore among the northern islands.   Santiago salvaged the mooring ring from the wreckage while trying to find proof of what had befallen his ship. Unlike most tied to the Curse Carrier, Santiago lived for another 20 years. During this time he served the Slatetop Union. His death is recorded as drowning, though his personal journals claim he never again went out to sea.