Blood Mage

You use Blood Magic as a means of achieving powers that would terrify a normal mage, increasing your destructive force and honing your archaic talents. To you, blood magic is not a barbaric power, but a tool to connect the very fabric of life.

Ensanguination

You've learned how blood works and how it flows in the body. At 1st level, if not already, you gain proficiency with the medicine skill.

Deeper Understanding

At 1st level, you have learned how to control your blood for its power. Immediately upon taking piercing or slashing damage, you may use hellish rebuke once per a long rest.

At 2nd level, immediately upon taking piercing or slashing damage, you may instead use a sorcery point to cast a cantrip, with a casting time of no more than 1 action, as a reaction.

Blood Sacrifice

Starting at 6th level when you cast a spell that deals damage you can raise the spell level by 1 or more by expending one or more hit die, lowering your hit point maximum by 2d8 per hit die expended. The blood magic is so strong that it can even raise it beyond what you are currently capable of casting. Your hit points are restored with a long rest.

The Blood Flows

At 14th level, you can expend one or more hit dice, up to your CHA modifier, to heal an ally within 30 feet as a bonus action. When doing so, your maximum hit points are reduced by a number equal to 1d8 per hit die expended, the ally heals double that amount. Your hit dice are restored upon a long rest.

You may also use a bonus action to take one or more hit die, up to your CHA modifier, from an ally within 30 feet as a bonus action. When doing so, the ally's hit point maximum is reduced by a number equal to 1 of their hit die per hit die expended and takes damage equal to it, you heal for double that amount. The ally's hit dice are restored upon a long rest.

Demonic Blood

Beginning at 18th level, you are able to reach into the Abyss and tie a demonic presence through you. You can spend half of your hit dice, taking equivalent damage, to become a demon with a CR equal to half your level rounded down. You can stay in this form for a number of minutes equal to your CHA modifier.

While in this form, as an action, you can spend 5 sorcery points to draw on this power and exude an aura of awe or fear (your choice) to a distance of 60 feet. For 1 minute or until you lose your concentration (as if you were casting a concentration spell), each hostile creature that starts its turn in this aura must succeed on a Wisdom saving throw or be charmed (if you chose awe) or frightened (if you chose fear) until the aura ends. A creature that succeeds on this saving throw is immune to your aura for 24 hours.