Source: Tasha's Cauldron of Everything
Wondrous item (tattoo), rare (requires attunement)
Produced by a special needle, this magic tattoo is dark in color and abstract.
Tattoo Attunement. To attune to this item, you hold the needle to your skin where you want the tattoo to appear, pressing the needle there throughout the attunement process. When the attunement is complete, the needle turns into the ink that becomes the tattoo, which appears on the skin.
If your attunement to the tattoo ends, the tattoo vanishes, and the needle reappears in your space.
Shadow Essence. You gain darkvision with a range of 60 feet, and you have advantage on Dexterity (Stealth) checks.
Shadowy Defense. When you take damage, you can use your reaction to become insubstantial for a moment, halving the damage you take. Then the reaction can't be used again until the next sunset.