Vampire's Shadow

Shadow Bond Escape.
When the Vampire's Shadow drops to 0 hit points away from its master, it wilts into the shadows, provided it isn't in running water or sunlight.  If there are no Shadows within 40 ft. for it to escape to it is destroyed.

While the Vampire's Shadow has 0 hit points in the shadows, it can't revert to corporeal form, and must reach it's host within 24 hours or be destroyed.  Once bonded again to the host Vampire, the Vampire's Shadow remains bonded with its Host until it has regained all of its health, regaining 1 Hit Point each hour.

Incorporeal Movement.
The Vampire's Shadow can move through other creatures and objects as if they were difficult terrain.  It takes 5 (1D10) force damage if it ends its turn inside an object.

Shadow Stealth.
While in dim light or darkness, the Vampire's Shadow can take the Hide action as a Bonus Action.

Shadow Stride.
As a bonus action, the Vampire's Shadow can step into a shadow within 5 feet of it and magically appear in an unoccupied space within 5 feet of a second shadow that is up to 60 feet away.  Both shadows must be cast by a Small or larger creature or object.

Sunlight Sensitivity.
While in sunlight, the Vampire's Shadow has disadvantage on attack rolls and on Wisdom (Perception) checks that rely on sight, and it takes 20 radiant damage at the start of its turn.

Amorphous.
The Vampire's Shadow can move through a space as narrow as 1 inch wide without squeezing.

Legendary Resistance (2/day) (If the Vampire's Shadow belongs to a Legendary Vampire).
If the Vampire's Shadow fails a saving throw, it can choose to succeed instead.

Strength Drain. Melee Weapon Attack: +8 to hit, reach 5 ft., one creature.  Hit: (4D8+4) necrotic damage.  The target's Strength is reduced by 1D6 The target dies if this reduces its Strength to 0.  Otherwise, the reduction lasts until the target finishes a long rest.  If a humanoid dies from this attack, a Shadow Horror rises from the corpse 1D10 hours later.

Multiattack.  The Vampire's Shadow makes three Claw attacks.

Claw. Melee Weapon Attack: +8 to hit, reach 10 ft., one target.  Hit: (3D6+4) slashing damage.  The target must succeed on a DC 16 Wisdom saving throw or be frightened of the Vampire's Shadow until the end of the target's next turn.

Lashing Shadows (Recharge 5-6).  Each creature within 60 feet of the Vampire's Shadow, except other Shadows or Vampires, must succeed on a DC 16 Dexterity saving throw or take 27 (6D8) necrotic damage.

Shadow Legion (1/Day). The Vampire's Shadow summons 2D4 Shadows provided the sun isn't up.  The summoned Shadows arrive in 1D4 rounds.

(If the Vampire's Shadow belongs to a Legendary Vampire)
The Vampire's Shadow can take 2 Legendary actions, choosing from the options below.  Only one legendary option can be used at a time and only at the end of another creature's turn.  The Vampire's Shadow regains spent legendary actions at the start of its turn.

Move.
The Vampire's Shadow moves up to its speed without provoking opportunity attacks.

Strength Drain (Costs 2 Actions).
The Vampire's Shadow makes one Strength Drain attack.

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Mythic Action Name (Costs # Actions). Enter the description for your mythic action.