Skulk

Medium monstrosity, Chaotic Neutral

Armor Class 14

Hit Points 18 (4d8)

Speed 30 ft.

STR 6 (-2)

DEX 19 (+4)

CON 10 (+0)

INT 10 (+0)

WIS 7 (-2)

CHA 1 (-5)

Saving Throws CON +2

Skills Stealth +8

Condition Immunities blinded

Senses darkvision 120 ft., passive Perception 8

Languages understands Common but can't speak

Challenge 1/2

Fallible Invisibility. The skulk is invisible. This invisibility can be circumvented by three things:

Charnel Candles
The skulk appears as a dim, translucent form in the light of a candle made of fat rendered from a corpse whose identity is unknown.
Children
Humanoid children, aged 10 and under, can see through this invisibility.
Reflective Surfaces
The skulk appears as a drab, smooth-skinned biped if its reflection can be seen in a mirror or on another surface.

Trackless. The skulk leaves no tracks to indicate where it has been or where it's headed.

Claw. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 6 (1d4 + 4) slashing damage plus 3 (1d6) necrotic damage.

Source

Mordenkainen Presents: Monsters of the Multiverse, p. 219