Blightroot Lich

Innate Spellcasting. The blightroot lich's innate spellcasting ability is Intelligence (spell save DC 17). It can innately cast the following spells, requiring no material components:

At will: chill touch, poison spray

3/day each: blight, cloudkill, animate dead

Legendary Resistance (3/Day). If the blightroot lich fails a saving throw, it can choose to succeed instead.

Rejuvenation. If the blightroot lich is destroyed, it regains all its hit points in 1d10 days unless its phylactery is destroyed.

Turn Resistance. The blightroot lich has advantage on saving throws against any effect that turns undead.

Multiattack. The blightroot lich makes two slam attacks.

Slam. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 3) bludgeoning damage plus 7 (2d6) necrotic damage.

Withering Touch. Melee Spell Attack: +9 to hit, reach 5 ft., one target. Hit: 21 (6d6) necrotic damage, and the target must succeed on a DC 17 Constitution saving throw or its hit point maximum is reduced by an amount equal to the necrotic damage taken. This reduction lasts until the target finishes a long rest.

The blightroot lich can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The blightroot lich regains spent legendary actions at the start of its turn.

Cantrip. The blightroot lich casts chill touch or poison spray.

Withering Touch (Costs 2 Actions). The blightroot lich uses its withering touch.

Animate Dead (Costs 3 Actions). The blightroot lich casts animate dead.