Shadar-Kai, Variant (5e Subrace)
From D&D Wiki
This is a different take on the elves of Shadowfell from the official subrace as presented in Mordenkainen's Tome of Foes.
Rather than focus on the hardier aspect of the shadow elves, this subrace sees them as tandem with the darkness. Wispy and lithe as shadows, they weave their way as attackers and roguish types, confusing enemies and making the most of the dark around them.
Ability Score Increase. Your Dexterity score increases by 1.
Shadow Former. You know the shadowcery cantrip. Additionally, starting 3rd level, you can cast the shadow blade spell once, as a 2nd-level spell. You regain use of this spell when you finish a long rest. Intelligence is your spellcasting modifier for these spells.
Dark Hunters. You have advantage in Dexterity (Stealth) and Wisdom (Survival) checks while in darkness.