Undead Fortitude. If damage reduces the zombie to 0 hit points, it must make a Constitution saving throw with a DC of 5 + the damage taken, unless the damage is radiant or from a critical hit. On a success, the zombie drops to 1 hit point instead.

Unusual Nature. Virdal doesn’t require air, food, drink, or sleep.

Legendary Resistance (1/Day). If the lich fails a saving throw, it can choose to succeed instead.

Rejuvenation. Virdal cannot Die, not until His Mother Valdeska Drakov is defeated in battle. If Virdal goes down his body returns within 1d4 hours

Turn Resistance. Virdal has advantage on saving throws against any effect that turns undead.

Multiattack. The necromancer makes three Arcane Burst attacks.

Arcane Burst. Melee or Ranged Spell Attack: +7 to hit, reach 5 ft. or range 120 ft., one target. Hit: 25 (4d10 + 3) necrotic damage.

Spellcasting. The necromancer casts one of the following spells, using Intelligence as the spellcasting ability (spell save DC 18):

At will: Toll The Dead, Inflict Wounds, Ray of Sickness, Chill Touch

3/day each: Bestow Curse, Dimension Door, Wither and Bloom

2/day each: Feign Death, Life Transference, Spirit Shroud

1/day: Circle of Death, Contagion. Blight

Summon Undead (1/Day). The necromancer magically summons five Skeletons Or Zombies. The summoned creatures appear in unoccupied spaces within 60 feet of the necromancer, whom they obey. They take their turns immediately after the necromancer. Each lasts for 1 hour, until it or the necromancer dies, or until the necromancer dismisses it as a bonus action.

Grim Harvest. When the necromancer kills a creature with necrotic damage, the necromancer regains 9 (2d8) hit points.

Virdal has one Lenegeary Action  that can be used at a time and only at the end of another creature's turn. Virdal regains spent legendary action at the start of his turn.

Disrupt Life (Costs 3 Actions). Each non-undead creature within 20 feet of the lich must make a DC 18 Constitution saving throw against this magic, taking 21 (6d6) necrotic damage on a failed save, or half as much damage on a successful one.