Oath of Blood

You have vowed to follow the teachings of The Blood God Salmak granting you a small fraction of his power. This grants the ability to control blood although if you do not have blood stashed away you will have to use your own witch for each level of the spell you'll have to take one more d6 of damage although this does not apply to all spells so you and your dm must diside what spells have that effect activate but the more you level up the more precisely you'll be able to control blood.

Bonus Proficiency

When you choose this domain at 1st level, you gain proficiency with Warhammer.

Blood Control

You can use you blood to heal 1d4 damage per short rest.

Pray

Every long rest you may pray to The Blood God and give him some blood and skulls for something your dm decides. 

Channel Divinity: Blood Clot

If the target fails a wisdom saving throw one limb is disabled the target will not get the use of the limb back until the succeed a wisdom saving throw or after 5 turns they lose it permanently. 

Poison Blood

Your blood is now like a poison if it gets into someone else body they will have to make a poison saving throw against it. You now also have advantage against poison saving throws.

Blood Steal

At 8th level, you gain the ability to infuse your weapon strikes with divine energy and take the targets blood and use it to cast the spells you and your dm decided will deal damage without taking damage. Once on each of your turns when you hit a creature with a weapon attack, you can cause the attack to deal an extra 1d8 radiant damage to the target. When you reach 14th level, the extra damage increases to 2d8.

Expanded Blood Vessels

Now that you have expanded blood vessels you may now preform a bonus action on your turn 5 times before needing to take a long rest to be able to use them again. You may not use 2 or more bonus actions in one turn.