Infernal Bloodline

The Infernal Bloodline bestows upon the Sanguimancer the essence of infernal power. Infused with the diabolic energy of the Nine Hells, enabling them to weave dark pacts and manipulate blood magic with a touch of diabolic influence.
Sign in Blood
At 3rd level, as an action, you can spend 3 Blood Points to establish a bond between yourself and a creature you can see within 30 feet. Until the end of your next turn, whenever you take damage, the linked creature takes the same amount of damage simultaneously. The connection persists for one minute or until either you or the bonded creature are incapacitated. As a bonus action, you can end this connection prematurely. You may expend a number of blood points, up to your constitution modifier, causing the creature to suffer 1d4 fire damage for each blood point expended this way.
Diabolic Pact
At 7th level, your understanding of the infernal bloodline allows you to strengthen the bond formed through your Blood Pact ability. When you use your Blood Pact ability you can spend an additional 3 Blood Points to forge a Diabolic Pact with a willing creature. You and the bonded creature gain the following benefits

• At the beginning of your turn, if you or the bonded creature are below half of your remaining hit points you may have each of you gain temporary hit points equal to your Constitution modifier. If a creature already has temporary hit points from this feature and gains more this way, the new temporary hit points do not stack but will refresh to equal your Constitution modifier.

• You and the bonded creature have advantage on saving throws and attacks.

Hellish Retribution
At 10th level, Your connection to the infernal bloodline grows stronger. When a creature damages you or the bonded creature affected by your Blood Pact, you can use your reaction to force the attacker to make a Constitution saving throw against your spell save DC. On a failed save, the attacker takes fire damage equal to the damage it dealt. You can use this ability a number of times equal to your proficiency bonus and regain all expended uses after a short or long rest.
Hellfire Pact
At 15th level your prowess with infernal bloodline contracts allows you to strengthen your alliance in the midst of battle. If you are bonded with a creature through Blood Pact, you can use an action to initiate the Hellfire Pact. For the next minute, you and the bonded creature gain the following benefits:

• You can communicate telepathically with each other as long as you are on the same plane of existence.

• If you are reduced to 0 hit points but not killed outright, the bonded creature can use its reaction to magically swap positions with you, taking the damage instead.

• Once during this duration each, when you or the bonded creature makes an attack roll or saving throw, you can roll a d6 and add the result to the roll.

Once you use this feature, you must finish a long rest before you can do so again.
Infernal Mastery
At 18th level, you reach the pinnacle of your infernal bloodline, you gain mastery over the dark arts of blood magic. As an action, you may spend 8 blood points to unleash a surge of infernal energy. For the next minute, your spells and abilities fueled by blood points deal an additional 1d6 fire damage per sanguimancer level.

Once you use this feature, you must finish a long rest before you can do so again.