These twisted dryads have been turned into vampiric monstrosities by undead warlocks and vampiric experiments.

Charred Dryads. With burnt and blackened skin, burnt twigs for hair, and clawed hands and feet that resemble burnt and twisted roots, mavkas seem scorched and even frail. Pupil-less red eyes gleam in their eye sockets with a hellish green flame.

Death Riders. All mavkas ride nightmare mounts as fearsome raiders, often snatching victims up into the saddle, never to be seen again. They despise and trample foot soldiers as peasants unworthy of attention.

Hag Killers. Mavkas are the mortal enemies of red hags, who call these undead horrors “greenbanes.”

Undead Nature. A mavka doesn’t require air, food, drink, or sleep.

Mavka

Medium undead, chaotic evil
Armor Class 17 (natural armor)
Hit Points 170 (20d8 + 80)
Speed 30 ft.

STR	DEX	CON	INT	WIS	CHA
20 (+5)	15 (+2)	18 (+4)	13 (+1)	13 (+1)	18 (+4)

Saving Throws Str +9, Dex +6, Con +8, Cha +8
Skills Athletics +9, Nature +5, Perception +5
Damage Resistances acid, fire, necrotic; bludgeoning, piercing, and slashing from nonmagical weapons
Damage Immunities cold, lightning
Senses darkvision 90 ft., passive Perception 15
Languages Common, Infernal, Sylvan
Challenge 12 (8,400 XP)

Innate Spellcasting. The mavka’s innate spellcasting ability is Charisma (spell save DC 16, +8 to hit with spell attacks). She can innately cast the following spells, requiring no material components:
Constant: protection from evil and good
At will: create or destroy water, dancing lights, ray of frost, resistance, witch bolt
3/day each: darkness, hold person, inflict wounds, invisibility, silence
1/day each: animate dead, bestow curse, blindness/deafness, contagion, dispel magic, vampiric touch

Nightmare Mount. A mavka is bonded to a nightmare when it is created. Mavkas are encountered with their mounts 95% of the time.

Sunlight Hypersensitivity. The mavka takes 20 radiant damage when she starts her turn in sunlight. While in sunlight, she has disadvantage on attack rolls and ability checks.

Actions

Multiattack. The mavka makes two slam attacks.

Slam. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 23 (4d8 + 5) bludgeoning damage plus 11 (2d10) necrotic damage.