Avatar of Death

Medium undead, neutral evil
Armor Class 20
Hit Points half the hit point maximum of its summoner
Speed 60 ft., fly 60 ft. (hover)
STR
16 (+3)
DEX
16 (+3)
CON
16 (+3)
INT
16 (+3)
WIS
16 (+3)
CHA
16 (+3)
Damage Immunities necrotic, poison
Condition Immunities charmed, frightened, paralyzed, petrified, poisoned, unconscious
Senses darkvision 60 ft., truesight 60 ft., passive Perception 13
Languages all languages known to its summoner
Challenge -

Incorporeal Movement. The avatar can move through other creatures and objects as if they were difficult terrain. It takes 5 (1d10) force damage if it ends its turn inside an object.

Turning Immunity. The avatar is immune to features that turn undead.

ACTIONS

Reaping Scythe. The avatar sweeps its spectral scythe through a creature within 5 feet of it, dealing 7 (1d8 + 3) slashing damage plus 4 (1d8) necrotic damage.

See the Deck of Many Things magic item.
Rules (Dungeon Master“s Guide)