Sources
CR
Type
Size
Alignment
Movement

Mormesk the Wraith

Medium Undead, Neutral Evil

Armor Class 13
Hit Points 45 (6d8 + 18)
Speed 0 ft., fly 60 ft.
STR
6
-2
DEX
16
+3
CON
16
+3
INT
12
+1
WIS
14
+2
CHA
15
+2
Damage Resistances acid, cold, fire, lightning, thunder; bludgeoning, piercing, slashing, from nonmagical attacks that aren't silvered
Damage Immunities necrotic, poison
Condition Immunities Charmed, Grappled, Paralyzed, Petrified, Poisoned, Prone, Restrained
Senses darkvision 60 ft., passive Perception 12
Languages Common, Infernal
Challenge 3 (700 XP)

Traits

Incorporeal Movement. The wraith can move through an object or another creature, but can't stop there.

Sunlight Sensitivity. While in sunlight, the wraith has disadvantage on attack rolls and on Wisdom (Perception) checks that rely on sight.

Actions

Life Drain. Melee Weapon Attack: +5 to hit, reach 5 ft., one creature. Hit:16 (3d8 + 3) necrotic damage, and the target must succeed on a DC 13 Constitution saving throw or its hit point maximum is reduced by an amount equal to the damage taken. If this attack reduces the target's hit point maximum to 0, the target dies. This reduction to the target's hit point maximum lasts until the target finishes a long rest.

Lore

A wraith is the incorporeal remnant of a particularly hateful being. Most wraiths can transform those they have slain into spectral undead servitors. Mormesk chooses not to, preferring to let the dead stay dead.