Briar, The Restrained Hunger

Crimson Curse. Briar's attacks cause the creature to bleed out. When Briar deals damage to a creature, it gains a stack of Crimson Curse for 3 turns, up to 3. Any creature afflicted with Crimson Curse takes 5 (2d4) necrotic at the start of their turn for each stack of Crimson Curse. Briar regains hitpoints equal to half the damage dealt by all instances of Crimson Curse.

Unarmed Strike. Melee Attack: +10 to hit, reach 5 ft., 1 target. Hit: 6 (1d6 + 3) bludgeoning or slashing damage. Applies a stack of Crimson Curse. 

Blood Frenzy (Recharge 5-6). Briar frenzies while fracturing her pillory, splitting it into two large scythe-like blades. For her next two turns including this one, Briar gains an additional 10 feet of movement speed. She uses all her movement speed to move to and attack the nearest enemy target. Briar makes three Blood Frenzy attacks each turn. Blood Frenzy attacks have a +14 to hit and deal 17 (2d8 + 8) slashing damage and apply a stack of Crimson Curse.

Snack Attack. Melee Weapon Attack: +20 to hit, 1 target. Hit: the target takes 13 (3d8) piercing damage and applying 3 stacks of Crimson Curse. Briar may only use this ability once while in a Blood Frenzy.

Chilling Scream. Ranged Spell Attack: Briar removes Blood Frenzy (if applicable). All creatures within a 15 foot cone of Briar must make a DC 16 Dexterity Saving throw as Briar releases a hemomancy-empowered scream. On a failed save, a creature takes 14 (4d6) necrotic damage and is stunned until the end of their turn. On a successful save, the creature takes half as much damage and is not stunned. If Briar removed Blood Frenzy to cast Chilling Scream, it instead deals 21 (6d6) necrotic damage. Briar heals for half of all the damage this ability deals.

Certain Death (Once per Long Rest). Ranged Weapon Attack: range 5000 feet. Briar kicks the hemolith gemstone in her pillory. The closest target within 10 foot wide line between Briar and a point within range must make a DC 15 Dexterity saving throw. If the target succeeds, the next closest target must make the saving throw. On a failed save, Briar teleports to the creature, dealing 22 (4d10) slashing damage, applying 3 stacks of Crimson Curse, and entering Blood Frenzy.