Burden of Time. Beasts and Humanoids (except elves) have disadvantage on saving throws while within 10 feet of the shadar-kai.
Fey Ancestry. The shadar-kai has advantage on saving throws against being charmed, and magic can't put it to sleep.
Spellcasting. The shadar-kai casts one of the following spells, requiring no material components and using Charisma as the spellcasting ability (spell save DC 16):
At will: arcane eye, mage armor, minor illusion, prestidigitation, speak with dead
1/day each: arcane gate, bane, confusion, darkness, fear, major image, true seeing
Multiattack. The shadar-kai makes three Shadow Spear attacks. It can replace one attack with a use of Spellcasting.
Shadow Spear. Melee or Ranged Weapon Attack: +8 to hit, reach 5 ft. or range 30/120, one target. Hit:7 (1d6 + 4) piercing damage plus 26 (4d12) necrotic damage. Hit or Miss:The spear magically returns to the shadar-kai's hand immediately after a ranged attack.
Misty Escape (Recharge 6–6). When the shadar-kai takes damage, it turns invisible and teleports, along with any equipment it is wearing or carrying, up to 60 feet to an unoccupied space it can see. It remains invisible until the start of its next turn or until it attacks or casts a spell.
In the gloom of the Shadowfell live shadar-kai, elves whose ancestors served the Raven Queen, a god of death and memory. They were brought to that realm in ages past, so long ago that they're now adapted to its cheerless environment, both physically and mentally.