Bere-gul Archfey Necrobotanist

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

Fey Ancestor. If a creature with the fey ancestry trait makes an attack against the Archfey, they must succeed a DC 15 Wisdom saving throw. If failed, their attack automatically fails. In additon, fey creatures or creatures with the fey ancestry trait have disadvantage on saving throws from spells cast by the Archfey.

Brave. The necromancer has advantage on saving throws against being frightened.

Brute. A melee weapon deals one extra die of its damage when the necromancer hits with it (included in the attack).

Indomitable (3/Day). The necromancer can reroll a saving throw it fails. It must use the new roll.

Keen Sight. The necromancer has advantage on Wisdom (Perception) checks that rely on sight.

Spellcasting. The necromancer is a 16th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 18, +10 to hit with spell attacks). The necromancer has the following wizard spells prepared:

Cantrips (at will): chill touch, dancing lights, mage hand, mending, minor illusion
1st level (4 slots): false life*, mage armor**, venomous ray*
2nd level (3 slots): blindness/deafness*, gust of wind, ray of enfeeblement*, web
3rd level (3 slots): animate dead*, bestow curse*, counterspell, lightning bolt
4th level (3 slots): banishment, blight*, dimension door, fire shield**
5th level (2 slots): arcane hand, cloudkill, wall of force
6th level (1 slot): create undead*
7th level (1 slot): finger of death*
8th level (1 slot): clone*

* Necromancy spell of 1st level or higher
** The necromancer casts these spells on itself before combat.

Grim Harvest (1/Turn). When the necromancer kills a creature that is neither a construct nor undead with a spell of 1st level or higher, the necromancer regains hit points equal to twice the spell's level, or three times if it is a necromancy spell.

Spellcasting. The Archfey is an 18th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 21, +12 to hit with spell attacks). The Archfey has the following Sorceror spells prepared:

Cantrips (at will): Fire Bolt, true strike, Ray of Frost

1st level (4 slots): Witch Bolt, Charm person, Thunderwave, Magic Missile

2nd level (3 slots): Enlarge/Reduce, hold person, invisibility, Misty Step

3rd level (3 slots): Fireball, counterspell, Lightning Bolt, Fear

4th level (3 slots): Dimension Door, Polymorph

5th level (3 slots): Dominate person, Wall of Stone

6th level (1 slot): Eyebite, Sunbeam

7th level (1 slot): Teleport, 

8th level (1 slot): Earthquake, Power Word Stun

9th level (1 slot): Gate

Magic Resistance. The Archfey has advantage on saving throws against spells.

Stunning Touch. Melee Spell Attack: +12 to hit, reach 5 ft., one creature. Hit: 10 (3d6) cold damage. The target must succeed on a DC 18 Constitution saving throw or be stunned until the end of the Archfey's next turn.

Rapier Attack. Melee weapon attack. +10 to hit, reach 5 ft., one creature. Hit: 1d8 piercing damage, plus 6d6 force damage.

Vampiric Touch. Melee Spell Attack: +10 to hit, reach 5 ft., one target. Hit: 10 (3d6) necrotic damage, and the necromancer regains hit points equal to half the necrotic damage dealt.

Leadership (Recharges after a Short or Long Rest) (must be able to speak). For 1 minute, the necromancer can utter a special command or warning whenever a nonhostile creature that it can see within 30 feet of it makes an attack roll or a saving throw. The creature can add a d4 to its roll provided it can hear and understand the necromancer. A creature can benefit from only one Leadership die at a time. This effect ends if the necromancer is incapacitated.

NECROTIC ARMOR FORM

Multiattack. The Archfey may make 2 attacks per turn.

Constrict. Melee Weapon Attack: +5 to hit, reach 10 ft., one target. Hit: 9 (2d6 + 2) bludgeoning damage, and a Large or smaller target is grapled (escape DC 13). Until this grapple ends, the target is restrained, and the undead can’t constrict another target. Any breathing creature may only breathe  5 rounds (30 seconds) in this condition before falling unconscious from suffocation.

Entangling Plants  Grasping roots and vines sprout in a 15-foot radius centered on the blight, withering away after 1 minute. Each creature of the blight’s choice in that area when the plants appear must succeed on a DC 12 Strength saving throw or become restrained. A creature can use its action to make a DC 12 Strength check, freeing itself or another entangled creature within reach on a success. 

Vines Ranged Attack: +6 to hit, range 40ft, one target. Hit: 9 (2d6+4) bludgeoning damage. If the target is size Medium or smaller, it is pulled 10 ft and is grappled (escape DC15) if the undead is not already grappling a creature.

Slash Melee Weapon Attack: +8 to hit, range 5ft, one target grappled by the undead. Hit: 18 (3d8+4) slashing damage and 4 (1d6) poison damage.  

The Archfey 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 Archfey regains spent legendary actions at the start of its turn.

Cantrip. The Archfey casts a cantrip.

Stunning Touch (Costs 2 Actions). The Archfey uses its Stunning Touch.

Charming Voice (Costs 2 Actions). The Archfey speaks to one creature it can see within 10 feet of it. The target must succeed on a DC 18 Charisma saving throw against this magic or become charmed for 1 minute. The charmed target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target's saving throw is successful or the effect ends for it, the target is immune to the Archfey's voice for the next 24 hours.

Mind Erosion (Costs 3 Actions). Each living creature within 20 feet of the Archfey must make a DC 18 Wisdom saving throw against this magic, taking 24 (7d6) psychic damage on a failed save, or half as much damage on a successful one.

Frighten Foe (Costs 2 Actions). The necromancer targets one hostile creature it can see within 30 feet of it. If the target can see and hear it, the target must succeed on a DC 16 Wisdom saving throw or be frightened until the end of the necromancer's next turn.
Cast a Spell (Costs 3 Actions). The necromancer casts a spell from its list of prepared spells, using a spell slot as normal.

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