Order of blood sorcery

Blood sorcerers sacrifice their own blood and life to cast spells in a method called sacrificial casting, limiting what they can cast, but casting it with great power.

Sacrificial casting

You use your own life and blood to cast your spells, using constitution as your casting modifier.  When you cast a spell 1st level or higher, instead of spending a spell slot, you roll hemocraft die equal to the spell’s level. You take necrotic damage equal to what you rolled (this damage cannot be reduced in any way). The enemy(s) targeted by the spell take half of this damage or heal half the health (whichever you chose) rounded up, however that damage can be reduced.  If the spell does not do damage or does not heal, it does whatever you chose. The level of spell you can cast depends on what hemocraft die you have d4=1st level spells, d6=2nd level spells, d8=3rd level spells, d10=4th level spells

 

Spells you cast in this way must come from either the necromancy or transmutation spell list, and you can prepare an amount of spells equal to your spell casting modifier plus your proficiency bonus

 

You know 2 cantrips when you take this subclass at 3rd level, and you gain another at 10th level

Transfusion

At 3rd level, you gain the ability to reap blood from creatures you kill with your spells. Once per turn when you kill one or more creatures with a spell of 1st level or higher, you regain hit points equal to twice the spell's level.  (This has no effect on creatures without blood)

Blood bending (novice)

 7th level- You gain the power to control the blood in another’s body.  You can cast any hold (creature) spell without the needed spell slot or spell in your prepared spell list, as long as it’s spell level is equal to half your blood hunter level (rounded down) PB times per day.  When you cast hold person in this way, the spell save changes from wisdom to constitution.

Blood manipulation

11th level- You can cast Polymorph without expending a spell slot. When you do so, you can target only yourself.

Once you cast Polymorph in this way, you can't do so again until you finish a short or long rest, though you can still cast it normally using an available spell slot.

Blood bending (expert)

15th level- Your control of another’s blood becomes refined bought to control another’s movement.  Your hold (creature) spells are now casted as dominate (creature) spells 

Boiling blood

18th level- You gain enough control over another’s blood to cause it to boil, you use an action to make the creature roll a constitution saving throw, or take 10d10 necrotic and 15d10 fire damage, halved on a successful save.  This has no effect on creatures without blood, and creatures below half heath have disadvantage on the saving throw