Vistra, Harbinger of the Black Advent

Rapid Shifting. Opportunity attacks made against Vistra, Harbinger of the Black Advent have disadvantage.

Ever-Watchful. As long as Vistra has two or more mechanical appendages attached to her back she cannot be surprised or flanked.

Armored. Each of Vistra's six mechanical appendages grants her a +2 to AC. These appendages can be attacked separately to lower Vistra's AC. An appendage has 16 AC and 30 HP, with resistance to slashing and piercing damage. They are considered sturdy (only a hit that deals at least 10 damage can damage it).

Short Circuit. Whenever Vistra is subjected to water or cold damage, she has to succeed on a DC 12 Constitution saving throw at the start of her turn, otherwise she can't take bonus actions, legendary actions, and reactions until the start of her next turn. Additionally, Vistra's speed is halved and she can't benefit from any bonus to her speed. While under this condition, a creature that touches Vistra or hits her with a melee attack while within 5 feet of her takes 7 (2d6) lightning damage and it must succeed on a DC 16 Constitution saving throw. On a failed save, a creature is flung away 10 feet from Vistra.

Lightning Rod. Whenever Vistra is subjected to lightning damage, she takes no damage and regains a number of hit points equal to half the lightning damage dealt. Additionally, the first time she hits with a melee attack on her next turn, the target takes an extra 2 (1d4) lightning damage.

Gifted Artificer. Vistra commands three eldritch constructs named Vigil, Inpetus, and Enthymema. Vigil and Enthymema move with Vistra, while Inpetus roams of its own volition. Each construct rolls its own initiative. AC and HP for each of the constructs can be found in the description below. Inpetus' stat block can be found within the homebrew catalogue.

Multiattack. Vistra makes two Claw attacks.

Claw. Melee Weapon Attack: +4 to hit, reach 10 ft., one target. Hit: 14 (4d6) slashing damage.

Harbinger's Ray. Vistra shoots a random ray from her appendages, choosing a target that she can see within 30 feet of her.

1. Paralyzing Ray. The targeted creature must succeed on a DC 16 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

2. Fear Ray. The targeted creature must succeed on a DC 16 Wisdom saving throw or be frightened for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.

3. Enervation Ray. The targeted creature must make a DC 16 Constitution saving throw, taking 21 (6d8) necrotic damage on a failed save, or half as much damage on a successful one.

4. Disintegration Ray. If the target is a creature, it must succeed on a DC 16 Dexterity saving throw or take 32 (8d8) force damage. If this damage reduces the creature to 0 hit points, its body becomes a pile of fine gray dust.

If the target is a Large or smaller nonmagical object or creation of magical force, it is disintegrated without a saving throw. If the target is a Huge or larger nonmagical object or creation of magical force, this ray disintegrates a 10-foot cube of it.

5. Sleep Ray. The target creature must succeed on a DC 16 Wisdom saving throw or fall asleep and remain unconscious for 1 minute. The target awakens if it takes damage or another creature takes an action to wake it. This ray has no effect on constructs and undead.

6. Death Ray (Recharge 5 - 6). The targeted creature must succeed on a DC 16 Dexterity saving throw or take 36 (10d6) necrotic damage. The target dies if the ray reduces it to 0 hit points.

Harbinger's Wrath (Recharge 6). Vistra charges a supersonic blast from within her chest. Until the start of her next turn, Vistra can't move or use any reactions and is concentrating on the charge.

At the start of the next turn, each creature in a 30-foot cone must make a Constitution saving throw. On a failed save, a creature takes 18 (6d6) thunder damage and is pushed 30 feet away from you. If a creature pushed by this ability hits a wall or another solid object, it takes an additional 4 (1d6) bludgeoning damage for every 10 feet it wasn't pushed. On a successful save, the creature takes half as much damage and isn't pushed.

In addition, unsecured objects that are completely within the area of effect are automatically pushed 30 feet away from Vistra by the ability's effect, and the Harbinger's Wrath emits a thunderous boom audible out to 600 feet.

If Vistra's concentration is broken before her next turn, the ability fails and the charge is lost.

Enthymema's Deflection. If Enthymema is still active, and Vistra makes a successful saving throw against a spell, or a spell attack misses her, Vistra can choose another creature (other than the spellcaster) she can see within 30 feet of her. The spell targets the chosen creature instead of Vistra. If the spell forced a saving throw, the chosen creature makes its own save. If the spell was an attack, the attack roll is rerolled against the chosen creature.

Vistra can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. Vistra regains spent legendary actions at the start of her turn.

Detect. Vistra makes a Wisdom (Perception) check.

Eldritch Quickdraw. Vistra targets one creature she can see within 30 feet of her and uses one of the Harbinger's Rays.

Slither. Vistra moves up to her movement without provoking opportunity attacks.

Quick Repair (Costs 2 Actions). If Vigil is still active, Vistra regains a number of hit points equal to 1d8 + 4.