Blood Moon Hemomancer

These sorcerers are born under a blood moon, absorbing some of its magic. Their magic is tied to the moon, becoming stronger during a full moon or a blood moon. They usually have some connection to the lower planes or other sources of dark energy. These sorcerers can only cast magic through the use of blood, most often their own, but they can also use the blood of others to cast their spells. When these sorcerers are born, they either have some physical deformities such as: antlers or horns, a tail, an extra limb or eye, a lib that resembles that of an animal a fin, a hoof, or they have very odd discolorations such as: their skin or hair being pure white, blood-red eyes, having permanent bruises all over their bodies, their teeth and fingers being pitch black. Tieflings, however, don't suffer from those physical abnormalities. While these sorcerers are a bit more limited in their spell repertoire, they more than make up for it with their powerful abilities.

Blood Magic

At lv 1 you gain Blood Magic: When you cast a spell you use HP instead of expending a spell slot, you can use your own HP, HP that has been lost by your allies and enemies or a combination of the two. When you cast a spell roll a d20 for lv1 spells, you add a d20 for every spell lv above 1, the result is the amount of HP you must expend to cast the spell. When you upcast a spell you add a d10 to the HP cost for every lv above the spells original lv. When you use metamagic instead of using sorcery points you can add a d10 to the HP cost. When you cast a spell you can expend any number of sorcery points to reduce the HP cost by 4 for every point spent but you can't reduce the cost bellow 6 * the spell's lv. When you convert a spell slot into sorcery points you regain HP equal to the number of sorcery points you gained. At lv 1 you chose 1 school of magic, you can only learn and cast spells from that school. At lv 9 and 15 you can choose 1 additional magic school and when you choose a school of magic you can learn 1 additional spell from that school. 

e.g. A lv1 spell would cost 1d20 HP, a lv9 spell would cost 9d20 HP but a lv1 spell upcast to lv9 would cost 1d20+8d10 HP. You and your party are fighting an orc, it has lost 5 HP and 1 of your allies has lost 5 HP. You can use those 10 HP to pay the cost of one of your spells, but when you cast the spell those 10 HP are used up.

Blood Manifestation

At lv 1 you gain Blood Manifestation: You can create any object using blood, so long as the quantity of blood matches the volume of the object being created. For example, creating a dagger would require a small amount of blood, 1 HP, but creating a  bridge that is a 100ft. long and  20ft. wide would require at least 100 liters of blood. Any weapon you create has the same stats as its regular counterpart, when using a created weapon you are treated as being proficient with it. The blood used for the creation of an object can't be used to cast spells. Small objects don't require any concentration, but they last for about an hour. Larger objects, those that require 10 to 50 liters of blood, require concentration and a CON check of 15 to maintain concentration when you stop concentrating on the object it dissolves. And objects that require more than 50 liters of blood also require a CON check of 20 to maintain concentration.

Blood Manipulation

At lv 1 you gain Blood Manipulation: You can manipulate the shed blood of friend and foe. When living enemies or allies lose HP, you can use that lost HP to fule 1 of 2 abilities. Once you use that HP for the ability that HP is used up, and can't be used again.

Blood Mend: Heal 1 friendly creature equal to the amount of lost HP, this can't exceed the creature's max HP. You can't use this ability on yourself. You can use this ability as either a standard or bonus action.

Blood Strike: You can deal damage to 1 creature equal to the amount of lost HP, impaling it with spikes made of blood. The damage type is slashing or piercing, your choice. You can use this ability as a standard action.

e.g. You and your party are fighting an orc, it has lost 5 HP and 1 of your allies has lost 5 HP. You can use those 10 HP to either heal your ally by 5 HP or deal 10 damage to the orc and once you do those HP can't be used for casting spells or using abilities, but any new HP that is lost can be used.

Blood Moon Magic

At lv 1 you gain Blood Moon Magic: Your magic is not only tied to blood but the moon as well. When its a full moon you can cast spells using your spell slots instead of HP, you can only use up to lv4 spell slots, you can't use lv5 or higher spell slots. When its a blood moon, however, you can freely cast spells using your spell slots and when you cast a spell using a spell slot roll a d20, on a roll of 20 you don't use up the spell slot. During a blood moon every turn of combat you regain 1 sorcery point and you can add any metamagic effect you want to spells you cast, even those you don't normally have.

Enhanced Vitality

At lv 6 you gain Enhanced Vitality: You gain +2 to CON, max 20. If you would drop to 0 HP, due to an attack or casting your spells, you can expend all your sorcery points and you are reduced to 1 HP. Immediately after this effect triggers, you can convert up to 3 spell slots to sorcery points. Your life span is increased by 100 to 600 years. Once per day you can convert up to 5 spell slots and gain double the sorcery points from that conversion.

Blood Shift

At lv6 you gain Blood Shift: Touch 1 willing creature and change its outward appearance into that of 1 creature whose blood you have, in your possession. The change also applies to the creature's voice, making the target sound the same as the creature whose blood you used. But this ability can't change the height of the creature, for example, you have the blood of a hill giant and you decide to transform a halfling into that hill giant. All you will get in that scenario is a hill giant the size of a halfling. You also can't transform bipeds into quadrupeds or vice versa. The effects of the ability last until the hemomancer releases it or the creature falls below 50% of its HP, this ability is unaffected by anti-magic fields or spells that dispel magic.

Blood Drain

At lv 6 you gain Blood Drain: Whenever a creature within 30ft. of you takes slashing or piercing damage, you can expend 3 sorcery points and, make it take an additional d4 damage for 3 rounds. This effect can't be applied to the same creature within the span of 6 rounds, after 6 rounds have passed you can apply the effect once again. At lv 10 the damage die becomes a d6, at lv 14 it becomes a d10 and at lv 18 it becomes a d12. You can purge bad blood form any willing creature, removing all conditions that creature is suffering but it looses half its current HP. You can also drain foreign blood from any creature, this includes the blood that a vampire has consumed.

Blood Control

At lv 14 you gain Blood Control: Expend 5 sorcery points and target 1 living creature, it must make a CON save with a DC of 20 if it fails the save it can instead reduce its HP to 10 to resist the effect. If it fails the save and doesn't reduce its HP, you gain full control over that creature's body. The effect lasts for 1d6 + your CON modifier rounds. You can control a number of creatures equal to your CON modifier. You must maintain concentration, or the effect ends early, targeting another creature with this ability doesn't break your concentration. After the ability ends or the creature resisted it, the creature gain immunity from this ability for the next 24 hours. During a full moon, the save DC is increased to 25 and during a blood moon, the only way to resist is by the HP reduction.

Blood Ritual

At lv 14 you gain Blood Ritual: Select and learn 3 ritual spells from any magic school you desire, if you already know a ritual spell you can learn 1 additional non-ritual spell from your chosen magic schools. Any material components can be replaced by either using 2 sorcery points per component or add a d10 to the HP cost per component. Any gold requirement adds 1 HP to the spell's cost for every 10 gp. You can also ignore verbal and somatic components of a spell by adding a 2d20 to the HP cost, or 1d20 to ignore either the verbal and somatic components. Any creature you target with a spell can reduce its HP by 3d20 and resist the spell, the exception being evocation spells.

Sanguine Devastation

At lv 14 you gain Sanguine Devastation: As a standard action, you can expend 5 sorcery points and use 1 of 3 abilities, you can also expend an additional 3 sorcery points to target 1 additional creature. These abilities only affect creatures that possess a heart and circulatory system. During a blood moon, by expending 3 sorcery points you can target up to 3 additional creatures and the save DC for these abilities is increased to 20.

Rip Their Hearts Out: Using your blood magic you can rip out the heart of a living creature. Target 1 creature, you can see, it must make a CON saving throw with a DC of 15 or it dies. You can expend an additional 5 sorcery points to impose disadvantage on the saving throw. If the creature makes its saving throw, it gains immunity from this ability for the next 24 hours.

Hear Stop: Using your ability to manipulate blood, you can make the heart of any creature you desire stop, even if it doesn't kill the creature it will still wreak havoc with its insides. Target 1 creature, you can see, it must make a CON saving throw with a DC of 15 or be reduced to 0 HP. If the target makes its saving throw, it is paralyzed for the next round. If the creature makes its saving throw, it gains immunity from this ability for the next 24 hours.

Bleed Out: Target 1 creature, you can see, it must make a CON saving throw with a DC of 15 or the next time it takes slashing or piercing damage, it suffers a d8 slashing or piercing damage for the next 4 rounds. If the target is suffering from the effects of your "Blood Drain" ability the damage die is increased to a d12. If you use this ability on a creature that is making death saving throws, it automatically fails 2 saving throws.

Blood Moon Rising

At lv 18 you gain Blood Moon Rising: Through your connection to the moon and its magic, you can call forth a blood moon. You channel your power and the day turns to night with a bright red moon where the sun should be if it is already night the moon becomes crimson. This lasts for 1 hour after the effect ends your CON score is halved for 1 month. You can use this ability once per month. At lv 20 your CON is halved for 1 week instead of 1 month and you can use this ability once every two weeks.