Cindersworn Dreadblade

Entropic Will. The Dreadblade’s attacks are infused with Seron’s power. Its weapon attacks ignore resistance to necrotic damage.

Weight of Finality. Creatures hit by the Dreadblade’s weapon attacks have their speed reduced by 10 feet until the end of their next turn as oppressive entropic force bears down on them.

Disciplined Ruin. The Dreadblade has advantage on saving throws against being charmed or frightened while it can see an allied Ashen Concord creature within 30 feet.

Ashen Presence. Enemy creatures within 10 feet of the Dreadblade have disadvantage on Charisma saving throws.

Multiattack. The Dreadblade makes three Voidblade attacks.

Red Voidblade.
Melee Weapon Attack: +9 to hit, reach 5 ft., one target.
Hit: 17 (2d8 + 5) radiant damage plus 13 (3d8) necrotic damage.
On a hit, the target must succeed on a DC 16 Constitution saving throw or have disadvantage on its next attack roll or saving throw before the end of its next turn.

Sever the Thread (Recharge 5–6).
The Dreadblade strikes with crushing inevitability. One creature within reach must make a DC 16 Constitution saving throw, taking 45 (10d8) necrotic damage on a failure, or half as much on a success.
On a failure, the creature cannot regain hit points until the start of the Dreadblade’s next turn.

Grim Advance. The Dreadblade moves up to half its speed toward a hostile creature it can see without provoking opportunity attacks.

Unyielding Retort. When a creature within 5 feet hits the Dreadblade with a melee attack, the Dreadblade makes one Red Voidblade attack against that creature.