Herald of Darkness

Made of Shadows (Shadow Form Only). The herald of darkness has resistance to bludgeoning, piercing, and slashing damage and can enter a hostile creature's space and stop there. In addition, it can move through a space as narrow as 1 inch wide without squeezing.

Shadow's Sight. Magical darkness doesn't impede the herald's darkvision.

Multiattack. The herald of darkness makes two Embrace Darkness or Shadow Sword attacks.

Embrace Darkness (Shadow Form Only). Melee Spell Attack: +7 to hit, reach 0 ft., one creature in the herald's space. Hit: 18 (3d8 + 5) necrotic damage, and the target must succeed on a DC 15 Constitution saving throw or be paralyzed until the end of its next turn.

Shadow Sword (Fiend Form Only). Melee Weapon Attack: +8 to hit, reach 10 ft., one target. Hit: 14 (2d8 + 5) slashing damage plus 9 (2d8) necrotic damage.

Majesty of the Abyss (Recharge 5-6). The herald of darkness emits a sinister burst of infernal power. Each creature within 15 feet of the herald and that can see it must make a DC 15 Constitution saving throw. On a failure, a creature takes 27 (6d8) necrotic damage and is blinded for 1 minute. On a success, a creature takes half the damage and isn't blinded. A creature that fails the saving throw by 5 or more is also paralyzed until the end of its next turn. A blinded creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

Shadow Shape. The herald magically transforms into a Large shadow or back into its true form, which is a Fiend. Its statistics are the same in each form. Any equipment it is wearing or carrying transforms with it. It reverts to its true form if it dies.