Sanguine Magic

Across cultures and throughout history, blood has been seen as the essence of life, and its spilling as a harbinger of death.  Though the magical properties of blood are acknowledged by even the most enlightened of arcane scholars, few are willing to fully explore its potential due to pervasive taboos stemming from its association with pain, horror, and violence.  Nevertheless, for those prepared to face ostracism and persecution--or at least keep their practices secret--blood magic provides an avenue to incredible magical power.  This power comes at considerable cost, however, as employing blood magic indeed requires one to shed blood, most often one's own.

Blood Sacrifice

At 2nd level, you have learned to use your own blood to empower the spells you cast. Most Sanguine Magic features require you to "sacrifice" one or more hit dice. Whenever you sacrifice a hit die, the following apply:

- You must be holding a one-handed weapon without the reach property that deals piercing or slashing damage, or some other implement that can be used to draw blood, such as a needle, a scalpel, or a shard of flint or glass. Many blood mages employ a spell focus designed for this purpose, such as a sharpened bone wand, a rod with a small concealed blade, or a staff intertwined with thorns. Your DM has final say on what may be used for this purpose.

- Each hit die sacrificed is considered spent and thus unavailable to use for healing after a short rest. Similarly, you cannot sacrifice hit dice that have already been spent on healing. Sacrificed hit dice are replenished along with spent hit dice when you complete a long rest.

- You take 1d6 necrotic damage for each hit die sacrificed.  This damage cannot be prevented or reduced in any way. If this damage reduces you to 0 hit points while you are casting a spell, the power of your sacrifice enables you to finish casting the spell before you fall unconscious.

When you cast a wizard spell using a spell slot of 1st level or higher, you may sacrifice one or more of your wizard hit dice to increase the effective level of the spell (as if you had cast it using a higher-level spell slot.) If the highest level spell slot you know is 1st level, you may sacrifice one hit die to cast a spell as if using a 2nd level spell slot.  Otherwise, each hit die sacrificed increases the effective level of the spell by one, to a maximum of the highest level spell slot you know.

Sanguine Rituals

Starting at 2nd level, you learn how to make a blood sacrifice to expedite the casting of ritual spells. By sacrificing a number of your wizard hit dice equal to the spell's level, you can cast a wizard spell as a ritual using the spell's normal casting time, rather than adding 10 minutes to it.

Alternatively, you can sacrifice other creatures to shorten the ritual casting time.  Once you begin the ritual, you must spend your action each round to either focus on casting the ritual, or to make an attack that deals piercing or slashing damage to a creature. If you take any other action, or if your attack fails to deal at least one point of piercing or slashing damage, the ritual fails and must be restarted. Once you have slain one or more creatures with total hit dice at least equal to the spell's level, you may complete casting the ritual using the spell's normal casting time. If you fail to slay sufficient creatures within 10 minutes of starting the ritual, it fails and must be restarted. Slain constructs, oozes, and undead do not count toward completion of the ritual, nor does any other creature that does not have blood (or a similar vital fluid.)

Exsanguinate

Starting at 6th level, you can siphon blood from nearby creatures when you make them bleed. When you deal piercing or slashing damage to a creature within 30 feet of you during your turn, you may use a bonus action to drain blood from the wound. You deal additional necrotic damage equal to 1d6 + your Intelligence modifier and you regain a number of hit points equal to the necrotic damage dealt. The creature must also make a Constitution saving throw against your spell save DC or suffer one level of exhaustion. This level of exhaustion is removed if the creature receives at least one point of magical healing. This feature has no effect on constructs, oozes, undead, or any other creature that does not have blood (or a similar vital fluid.)

You can use this feature a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.

Summon Homunculus

Beginning at 10th level, you are able to temporarily create a homunculus crafted from only your own blood. As an action, you use this feature to sacrifice one wizard hit die and the creature, which has the same statistics as the homunculus described in the Monster Manual, appears in a space within 5 feet of you. You may also choose to sacrifice any number of your remaining wizard hit dice as you summon the homunculus in order to grant it temporary hit points equal to the necrotic damage you take. After one hour, or if you or the homunculus dies, it dissolves into a puddle of blood. If you spend a bonus action and touch the homunculus before this happens, you can dismiss the creature early and regain a number of hit points equal to any temporary hit points it has remaining from when you summoned it.

If you already have a homunculus companion (such as from casting the Create Homunculus spell,) using this feature does not create a new one. Instead, it teleports your homunculus to a space within 5 feet of you, and you may sacrifice wizard hit dice as you do so to grant it temporary hit points equal to the necrotic damage you take. The homunculus can be summoned this way from any distance, but if it is on another plane of existence then using this feature has no effect.

You can use this feature once, then you must finish a short or long rest before you can use it again.

Blood Boil

At 14th level, you are able to agitate the blood of creatures around you, causing it to become painfully hot. As an action, you sacrifice one wizard hit die for each creature you can see within 30 feet of you that you choose to be affected. Each affected creature must make a Constitution saving throw against your spell save DC or take necrotic damage equal to 1d6 plus your Intelligence modifier and become frightened for 1 minute. A creature that succeeds on the saving throw takes half damage and is not frightened. While frightened by this feature, a creature takes 1d6 necrotic damage at the start of each of its turns, wastes its action writhing in agony, and must use all of its movement to get as far away from you as possible. A frightened creature can repeat the saving throw at the end of each of its turns, ending the frightened condition on itself on a success. This feature has no effect on constructs, oozes, undead, or any other creature that does not have blood (or a similar vital fluid.)

You can use this feature once, then you must finish a long rest before you can use it again.