Blood Mages are descendants of some sort of powerful entity or entities. They may have descended from celestials, devils, demons, or something else that is entirely unknown.

Many of them have parents and or siblings who were born as powerful sorcerers, but they themselves did not manifest any sort of magical abilities. Thus, through trial and error, they have learned how to pull the power out of their blood, and use this to alter the world around them. They can even temporarily sacrifice some of their own life force in order to power their spells further.

Additional Spells

At the indicated levels below, you gain the following additional known spells.

You cannot change them, and they do not count towards your sorcerer spells known.

1st level: False Life, Inflict wounds

3rd level: Dark Vision, Arcanist's Magic Aura

5th level: Bestow Curse, Vampiric Touch

7th level: Blight, Death Ward

9th level: Contagion, Telepathic Bond

Sanguine Power

1st-level Blood Mage feature

The Blood mage gains an extra Sorcerer hit die at sorcerer levels 1, 6, 14, and 18. This does not increase their maximum hit points.

Blood mages can spend their sorcerer hit dice to power their abilities. They cannot use other hit dice gained by multiclassing. Hit dice spent in this way can only be restored by finishing a long rest, by a wish spell (not a standard use of wish and will cause stress), or by Divine Intervention. Until then, they are spent and cannot be used in any way.

Overpower Spell

1st-level Blood Mage feature

The blood mage can increase the power of their spells at the temporary cost of their own life force.

When one of your spells damages an enemy, as a Blood Mage, you can choose to roll a number of your Sorcerer hit dice up to your proficiency bonus, and add it to the damage against one target. A critical hit will not double these dice.

Sacrificial Healing

6th-level Blood Mage feature

As an action, the Blood Mage can touch someone and roll a number of their sorcerer hit dice up to their proficiency bonus in order to heal their targert. This can heal anything that has hit points, including constructs and undead.

Sacificial Boost

6th-level Blood Mage feature

When the Blood mage fails a saving throw, as a reaction, they can roll and spend one of their hit dice in order to add it to the saving throw.

Blood Sacrifice

14th-level Blood Mage feature

During a short rest, the Blood Mage can roll one of their Sorcerer hit dice in order to restore sorcery points instead of hit points.

Doing so requires great concentration and causes a good amount of stress, such that you can gain no other benefits of a short rest while doing this.

Greater Overpower Spell

18th-level Blood Mage feature

 When you overpower a spell (see the 1st level feature), the additional damage affects all creatures damaged by the spell.