Usekh of the Dragon (5e Equipment)
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Wondrous item, rare (requires attunement)
This item is a broad collar made of precious metals and set with gems of a uniform color. When worn, the clasp is magically sealed, and the collar cannot be removed by any hand other than your own. The collar features detailed engravings of dragons, and is lined with subtle draconic script.
The Usekh of the Dragon is often used by cults of Tiamat to bring more dedicated servants into their ranks, or reward their more zealous members with true draconic power to better serve their goddess.
Breath Weapon. While attuned to the Usekh of the Dragon, you gain the dragonborn's Breath Weapon trait, the type of which is determined by the color of the gems in the collar. You may use this effect twice, and you regain all expended uses at dawn.
Cursed. While attuned to the Usekh of the Dragon, each time you take a long rest, you must make a DC 16 Constitution saving throw. On a failure, you begin to mutate into a dragonborn of the same ancestry as the collar's color. For each failed save, exchange one racial trait of your original race with a racial trait from the dragonborn race. When there are no racial traits left to exchange, the transformation is finished, and you no longer make constitution saving throws at the end of a long rest.
After the transformation is complete, and every day thereafter, you must make a DC 12 Charisma saving throw. If you fail, your alignment changes by one step toward evil. If your alignment is already evil when you fail this check, you are struck with a constant and pervasive compulsion to seek out and serve an evil dragon.