Chalstor, The Reaper

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

Reaper. When Chalstor, The Reaper casts a necromancy cantrip that normally targets only one creature, it can instead target two creatures within 5ft of each other.

Innate Spellcasting. Chalstor, The Reaper's innate spellcasting ability is Wisdom (spell save DC 20, +14 to hit with spell attacks). Chalstor, The Reaper can innately cast the following spells, requiring no material compoments:

At will: detect magic, dispel magic (as a 4th level spell), spirit guardians
3/day each: cause fear, tasha's hideous laughter
1/day each: invisibility, misty step

Spellcasting. Chalstor, The Reaper is a 20th level spellcaster. His spellcasting ability is Wisdom (spell save DC 20, +14 to hit with spell attacks). Chalstor, The Reaper has the following cleric spells prepared:

Cantrips (at will): toll the dead, guidance
First Level (4 slots): inflict wounds, ray of sickness, tasha's hideous laughter
Second Level (3 slots): hold person, silence, blindness/deafness
Third Level (3 slots): animate dead, revivify, vampiric touch
Fourth Level (3 slots): banishment, blight, death ward
Fifth Level (3 slots): antilife shell, contagion, hallow
Sixth Level (2 slots): create undead, harm
Seventh Level (2 slots): divine word, resurrection
Eighth Level (1 slot): antimagic field
Ninth Level (1 slot): gate, true resurrection

Multiattack. Chalstor, The Reaper may cast one leveled spell, then casts toll the dead twice.

Soul Sunder (Recharge 6). Chalstor, The Reaper chooses 10 creatures it can see within 90 feet. those creatures must make a DC 18 Wisdom saving throw or become sundered for one minute.

A sundered creature has disadvantage against all saving throws, and may not move further than 180 feet away from the source of their sundering.

Reaper's Step. As a reaction when a creature dies within 120 feet of Chalstor, The Reaper, Chalstor, The Reaper teleports to any space within 5 feet of the dying creature.

Chalstor, The Reaper 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 death cleric regains spent legendary actions at the start of its turn.

Detect. Chalstor, The Reaper makes a Wisdom (Perception) check.

Toll the Dead. Chalstor, The Reaper casts Toll the Dead.

Necrotic Preparation (Costs 3 Actions). Chalstor, The Reaper recharges it's Soul Sunder ability.