Shadow Spirit

Medium Monstrosity, Unaligned

STR
13 (+1)
DEX
16 (+3)
CON
15 (+2)
INT
4 (-3)
WIS
10 (+0)
CHA
16 (+3)
Terror Frenzy (Fury Only).

The spirit has advantage on attack rolls against frightened creatures.

Weight of Sorrow (Despair Only).

Any creature, other than you, that starts its turn within 5 feet of the spirit has its speed reduced by 20 feet until the start of that creature's next turn.

Actions

Multiattack.

The spirit makes a number of attacks equal to half this spell's level (rounded down).

Chilling Rend.

Melee Weapon Attack: to hit, reach 5 ft., one target. Hit: 1d12 + 3 + the spell's level cold damage.

Dreadful Scream (1/Day).

The spirit screams. Each creature within 30 feet of it must succeed on a Wisdom saving throw against your spell save DC or be frightened for 1 minute. The frightened creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Bonus Actions

Shadow Stealth (Fear Only).

While in dim light or darkness, the spirit takes the Hide action.

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Shadow Spirit

Source: Tasha's Cauldron of Everything, p. 114 - Licenses and attribution