Torque of the Sea:

This item is a hinged, decorated gold collar, worn as decoration around the neck. Kromyn created it to allow the wearer to breathe water indefinitely.
The Torque is activated whenever the wearer is submerged in water; it automatically casts a variant Water Breathing spell on the Wearer, causing him to grow gill slits on his neck beneath the Torque. The spell's duration is 1 hour, but is recast every hour by the Torque for as long as the wearer is under water. If the wearer leaves the water before the spell expires, the Torque magically permits him to breathe air until the gills vanish; removing the Torque before this time causes the wearer to begin "drowning" (see below).

The Torque has an unfortunate side effect; each time the Water Breathing spell is cast, the DM makes a secret percentage roll. On a result of 1-84%, the spell lasts for 1 hour, as normal, but a roll of 85-100% means that the spell is permanent. Those afflicted with permanent gills are unable to breathe out of water unless wearing the Torque; without it, they "drown" in air, taking 1d6 damage per round until dead. The gills may be dispelled by a Dispel Magic cast by a 20th+-level Mage, or by a Wish; otherwise, they cannot be removed.

Kromyn made ten of these devices, all with the same side effect; by the time of his "death" in 896 AY, a colony of roughly 80 unwillingly-gilled humans and demihumans, calling themselves "the Torquera", had been formed off the shores of Alphatia. Any children born to the Torquera have a 90% chance of being gilled water-breathers themselves (the remaining 10% are left on-shore, to be adopted by nearby fishing villages), so the colony has grown considerably since then, to nearly 12,000; The racial makeup of the Torquera is roughly 70% human, 20% Elf and 10% Halfling - called Humoi, Elvai and Hindari, in the debased Torquera tongue. The classes and abilities of the Torquera are the same as their surface-dwelling relatives, although the spells used by Clerics and Mages have altered somewhat.

The sinking of Alphatia resulted in the deaths of 65% of the Torquera still living in their original settlement (about 30% of the total populace). The remainder of that branch of the race have since moved into the flooded lower caverns of Monster Island. The Torquera retain four of the Torques, one for each major settlement (the Monster Islanders had a second, but it was lost during the sinking), which they use both to send emissaries above the waves, and to gain "new blood" for their race. The location of the remaining five Torques is unknown.