Spellcasting. The Undertaker is a 18th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 18, +9 to hit with spell attacks). The necromancer has the following wizard spells prepared:

Cantrips (at will): chill touch, dancing lights, ray of frost, mage hand, mending, shocking grasp

1st level (4 slots): false life*, mage armor, ray of sickness*, shield

2nd level (3 slots): blindness/deafness*, misty step, ray of enfeeblement*, scorching ray, web

3rd level (3 slots): animate dead*, bestow curse*, counterspell, Dispel Magic, fireball, summon undead*, vampiric touch*

4th level (3 slots): blight*, dimension door, stoneskin

5th level (2 slots): Bigby’s hand, cloudkill, seeming, danse macabre

6th level (1 slot): circle of death*, contingency, create undead*, disintegrate, 

7th level (1 slot): finger of death*, plane shift, power word pain, simulacrum, teleport

 8th Level (1 slot): Clone

9th Level (1 slot): True Resurrection 

*Necromancy spell of 1st level or higher

Grim Harvest (1/Turn). When The Undertaker 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.

Fists. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit: 10 (2d6 + 6) bludgeoning damage. 

 Eye Roll. The undertaker's eyes have the ability to go white, illuminating a eerie white glow. 

Sit Up - When Knocked Prone, The Undertaker can use a reaction to sit up forcing all enemies within a 10 foot radius to move backwards 5 feet. The reaction finishes with The Undertaker standing.

Choke Slam. Melee Attack: +10 to hit, reach 5 ft., one creature. Hit: 25 (4d6 + 8) bludgeoning damage. The Undertaker grabs target by the neck, raises them overhead by one arm and drives their body into the ground. On hit the target must make a DC20 constitution saving throw. On fail, the target Knocked prone and stunned for their next turn.  

Tombstone Piledriver. Melee Attack: +10 to hit, reach 5 ft., one creature. Hit: 25 (4d6 + 8) bludgeoning damage. The Undertaker grabs target, picks them up, inverts their body and drives their skull into the ground. The Undertaker then places their hands in a "prayer pose" before releasing the target. On hit the target must make a DC20 constitution saving throw. On fail, the target Knocked prone and stunned for their next turn.