You have been touched by a being of the upper planes and some of their power has merged with your own mortal form.
Cloak of Stars. As an action, you wrap yourself in a starry cloak, appearing like a silhouette formed of the night sky. When you do, attack rolls have disadvantage against you. This cloak lasts for 1 minute, until you dismiss it (no action required), or until you become incapacitated. Once you use this trait, you can’t use it again until you finish a long rest.
Nyxborn Resistance. You have resistance to necrotic and radiant damage.