Amorphous.

The shadow can move through a space as narrow as 1 inch wide without squeezing.

Shadow Stealth.

While in dim light or darkness, the shadow can take the Hide action as a bonus action. Its stealth bonus is also improved to +6.

Sunlight Weakness.

While in sunlight, the shadow has disadvantage on attack rolls, ability checks, and saving throws.

Actions

Strength Drain.

Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 9 (2d6 + 2) necrotic damage, and the target's Strength score is reduced by 1d4. The target falls unconscious if this reduces its Strength to 0. The creature regains consciousness and the reduction to its Strength score disappears after it finishes a short or long rest.

Detached Shadow