Though they are all retributive or even vengeful, gods of the Blood Domain are as varied as the reasons people spill blood itself. Some, like the good-aligned Ilmater and Torm, are unyielding vindicators of harm and pain, keeping their martyr-like followers' spilt blood to weigh against the torment of those who wronged them. Most blood gods, such as Mogis, Ares, Erythnul, Khorne, The Mockery, and Sargonnas, are deities of slaughter that demand their followers wage bloody war and take no prisoners. Many are deities of pain and murder, like Iuz, Loviatar, Bhaal, or Khaine. Most clerics of a blood god give blood sacrifices to their deity, and some blood gods are neutral deities of the art of blood sacrifice, who view blood as simply the most sacred of all currencies.

Domain Spells

CLERIC LEVEL	SPELL
1st	blood reading (new), inflict wounds
3rd	carnage blast (new), infuse blood (new)
5th	life transference*, vampiric touch
7th	agonize (new), hemorrhage (new)
9th	bend blood (new), grim terror (new)

D&D Beyond Note: New homebrew spells and spells marked with an asterisk must be selected manually in the character builder. Homebrew spells must first be added to your collection.

Acolyte of Humors

At 1st level, you gain proficiency in the Medicine skill, and you learn the new blood boil cantrip, which is a cleric cantrip for you and doesn't count against the number of cantrips you can know as a cleric.
D&D Beyond Note: New homebrew spells must be added to your collection and then selected manually in the character builder.

Blood Rites

Also at 1st level, you learn how to channel power beyond your limits by sacrificing your own blood for divine power.

As a bonus action, you can spill your blood and spend up to 5 of your remaining hit dice, but you do not regain hit points. Instead, you take 1d8 necrotic damage per hit dice expended; this ignores resistances and immunities.

The next cleric spell you cast on this turn is also a Blood spell in addition to its other schools and does not require a spell slot if it would normally expend a spell slot of a level equal to or less than the number of hit dice you expended. If the casting time is 1 bonus action, you can cast the spell as part of using this feature.

However, the spell can't restore a dead creature to life. Also, unless it is a necromancy spell, it can't cause any creature to regain hit points; instead of restoring hit points, it grants temporary hit points equal to half as many hit points as it would have restored.

You can't use this feature to cast a spell at a level higher than you have spell slots for, and you can't expend more hit dice using this feature than half your cleric level before finishing a long rest.

Channel Divinity: Holy Sacrifice

Starting at 2nd level, you can use your Channel Divinity to sacrifice your enemies' life force to your divinity in return for favor and blessings.

As a reaction when a creature you can see within 60 feet of you is reduced to 0 hit points, you can present your holy symbol to sacrifice its life force. Choose either yourself or the creature that reduced the target to 0 hit points. The chosen creature regains hit points equal to your proficiency bonus + twice your cleric level. This can't restore a creature to more than half its hit point maximum or restore hit points to undead or constructs.

You gain any excess hit points as temporary hit points that last until the end of your next turn.

Channel Divinity: Blood Vengeance

Starting at 6th level, you can use your Channel Divinity to pray over your allies' spilt blood, gaining the power needed to achieve proper vengeance.

As a reaction when a creature within 60 feet of you that has blood takes slashing, bludgeoning, or piercing damage, or damage from a Blood spell, you can present your holy symbol to imbue the creature with the divine power taken from its blood. Until the end of the target's next turn, it has advantage on attack rolls, and the first time it hits with an attack and deals damage, it deals extra damage equal to 5 + your cleric level.

Potent Spellcasting

Starting at 8th level, you add your Wisdom modifier to the damage you deal with any cleric cantrip.

Miraculous Blood

At 17th level, your blood is affected by a miraculous blessing of healing power. The blessing can restore a total number of hit points equal to your cleric level × 5. When you finish a long rest, the blessing replenishes, and you can also choose to touch a willing creature that has blood and lend the blessing to it. Until you die or finish a long rest again, that creature is affected by the blessing instead of you.

Whenever the creature with the blessing takes slashing, bludgeoning, or piercing damage, damage from a Blood spell, or necrotic damage from expending its hit dice for blood magic, it can choose one other creature within 30 feet of it. The other creature regains an amount of hit points equal to half the damage taken, up to the maximum amount remaining in the blessing.

Undead and constructs are immune to this feature.