Blood Propagator

Blood Propagators are strange undead spirits that are highly sought after. They are often hunted by more powerful undead to be used to resource gathering. When the propagator eats enough blood and flesh they turn it into a crystalline material within their body which they then expell. Their tails are made out of this razor-sharp crystal which they can use as a weapon.

Blood Propagator CR: 9

Large undead, lawful evil

Armor Class: 20 (Natural Armor

Hit Points: 153 (18d10 + 54)

Speed: 20 ft , burrow: 20 ft , swim: 40 ft

STR

18 +4

DEX

8 -1

CON

16 +3

INT

8 -1

WIS

14 +2

CHA

8 -1

Saving Throws: STR +7, CON +6, WIS +5

Skills: Perception +5, Survival +5

Damage Resistances: Bludgeoning, Piercing, and Slashing from Magic Weapons

Damage Immunities: Necrotic, Poison; Bludgeoning, Piercing, and Slashing from Nonmagical Attacks

Condition Immunities: Blinded, Charmed, Exhaustion, Frightened, Poisoned

Senses: Blindsight 120 ft, Passive Perception 15

Languages: Common

Challenge Rating: 9

Proficiency Bonus: +4

Regeneration. When the propagator bites a creature, it heals the amount of damage that the target took.

Crystalline Death. When the propagator is reduced to 0 hit points; the blood and crystalline spikes in their bodies explode out. Any creature within 30 feet of the corpse must make a Dexterity saving throw DC 15. On a failure, they take 3d6 piercing damage and 5d6 necrotic damage. On a success, they take half damage.

Actions

Multiattack. The propagator can make one bite and one tail attack or one bite and one crystalline spike attack.

Bite. Melee Weapon Attack: +8 to hit, reach 5 ft., 1 target. Hit: 10 (2d6 + 4) [piercing] damage plus Wounding Bite. The damage that the bite causes can not be healed by magical or mundane means. The Target can only heal this damage once they receive the effects of a remove curse spell.
Tail. Melee Weapon Attack: +8 to hit, reach 10 ft., 1 target. Hit: 13 (3d6 + 4) [bludgeoning] damage.
Crystalline Spike. RangedWeapon Attack: +3 to hit, range 5/100 ft., 1 target. Hit: 9 (2d10 -1) [piercing] damage plus 12 (4d6) necrotic damage

The Blood Propagators are giant undead leeches with bulbous bodies. Their sucker-filled mouths are constantly seeking to eat and nourish their bodies. At the end of their slimy, hard bodies are crystalline spikes that end their tails.
These undead spirits are highly sought after due to the byproduct they produce when they eat flesh and blood. When they devour enough raw materials (Flesh and blood) they produce a crystal that is red and often sharp. This is sharp and durable and can be used to craft weapons. Their tail spikes are made of this blood-red crystalline. The purer their diet, the better the quality of the crystalline.