Base Class: Fighter
Just read the short one
Hemocraft magic
After picking this subclass at 3rd level, you gain access to one Blood Curse of your choice. Additionally, you gain access to a Hemocraft Die, which are used for some of your class features. This die starts as a d4, and is raised to a d6 at 7th, d8 at 10th, and d10 at 15th level respectively.
When casting a Blood Curse, you can choose to amplify it, but only before the target is affected. When doing this, you take damage equal to the roll of your Hemocraft Die. This damage is necrotic and cannot be reduced/negated in anyway.
Using the Hemocraft Die, you can invoke a Crimson Rite, which provides an elemental affinity to your weapon until the end of a short or long rest. When applying this effect, you take damage equal to the roll of your Hemocraft Die. This damage is necrotic and cannot be reduced/negated in anyway. Once the rite is applied, your weapon is considered magical, dealing damage of the type you choose equal to that of your Hemocraft Die. You learn one rite now, and learn an additional one at 10th level. Only one rite may be applied at a time, and only a weapon you wield can hold a rite. You may change these rites only when you take a level in the Fighter class.
Hemocraft DC = 8 + Proficiency + Intelligence Modifier
Crimson Rites:
Rite of the Flame. Your rite damage is fire damage.
Rite of the Frozen. Your rite damage is cold damage.
Rite of the Storm. Your rite damage is lightning damage.
Rite of the Dead. Your rite damage is necrotic damage. (Prerequisite: 10th level)
Rite of the Oracle. Your rite damage is psychic damage. (Prerequisite: 10th level)
Rite of the Roar. Your rite damage is thunder damage. (Prerequisite:10th level)
Curses
Blood Curse of the Anxious
As a bonus action, you harry the body or mind of a creature within 30 feet of you, making them susceptible to forceful influence. Until the end of your next turn, Charisma (Intimidation) checks made against the cursed creature have advantage.
Amplify. The next Wisdom saving throw the cursed creature makes before this curse ends has disadvantage.
Blood Curse of Binding
As a bonus action, you attempt to bind a Large or smaller creature you can see within 30 feet of you, which must make a Strength saving throw. On a failure, the cursed creature’s speed is reduced to 0 and it can’t use reactions until the end of your next turn.
Amplify. This curse lasts for 1 minute and can affect any creature regardless of size. The cursed creature can repeat the saving throw at the end of each of its turns, ending the curse on itself on a success.
Blood Curse of Bloated Agony
As a bonus action, you curse a creature that you can see within 30 feet of you, causing its body to swell until the end of your next turn. For the duration, the creature has disadvantage on Strength checks and Dexterity checks, and takes 1d8 necrotic damage if it makes more than one attack during its turn.
Amplify. This curse lasts for 1 minute. The cursed creature can make a Constitution saving throw at the end of each of its turns, ending the curse on itself on a success.
Blood Curse of Exposure
When a creature you can see within 30 feet of you takes damage from an attack or spell, you can use your reaction to temporarily weaken its resilience. Until the end of the target’s next turn, it loses resistance to all the damage types dealt by the triggering attack or spell (including for that triggering effect).
Amplify. The target instead loses invulnerability to the damage types of the triggering attack or spell, but has resistance to those damage types until the end of its next turn.
Blood Curse of the Eyeless
When a creature you can see within 30 feet of you makes an attack, you can use your reaction to roll one hemocraft die and subtract the number rolled from the creature’s attack roll. You can choose to use this feature after the creature’s roll, but before the DM determines whether the attack hits or misses. The creature is immune to this curse if it is immune to the blinded condition.
Amplify. You apply this curse to all the creature’s attack rolls until the end of the creature’s turn. You roll separately for each affected attack.
Blood Curse of the Fallen Puppet
When a creature you can see within 30 feet of you drops to 0 hit points, you can use your reaction to instill that creature with a final act of aggression. The creature immediately makes one weapon attack against a target of your choice within its range.
Amplify. You can first cause the cursed creature to move up to half its speed, and you grant a bonus to its attack roll equal to your Hemocraft modifier (minimum of +1).
Blood Curse of the Marked
As a bonus action, you mark a creature that you can see within 30 feet of you. Until the end of your turn, whenever you hit the cursed creature with a weapon for which you have an active crimson rite, you roll an additional hemocraft die when determining the extra damage from the rite.
Amplify. The next attack roll you make against the target before the end of your turn has advantage.
Blood Curse of the Muddled Mind
As a bonus action, you curse a creature that you can see within 30 feet of you that is concentrating on a spell or using a feature that requires concentration. That creature has disadvantage on the next Constitution saving throw it makes to maintain concentration before the end of your next turn.
Amplify. The cursed creature has disadvantage on all Constitution saving throws made to maintain concentration until the end of your next turn.
Branding
Upon reaching 7th level, you have learned how to brand your enemies with your blood magic. When you damage a creature with a weapon that has an active Crimson Rite, you may spend a free action to brand that target. You always know the direction of the creature as long as you are on the same plane of existence. Additionally, any time the creature is damaged by either you or a target you can see within 5ft of you, they take psychic damage equal to your intelligence modifier (minimum of 1). The brand remains until either you choose to dismiss the brand, brand another creature, or the spell Dispel Magic is cast on you. The brand's "spell level" is equal to half your fighter level (maximum 9th).
Once you use this feature, you cannot use this feature again until after a short or long rest.
Additionally, you gain access to an additional Blood Curse
Grim Augmenting
Starting at 10th level, your Hemocraft has begun to change your body more physically. Your speed increases by 5ft, and you gain a bonus to Strength and Constitution saving throws equal to your Intelligence Modifier.
Additionally, you gain access to an additional Blood Curse
Tethering Brand
At 15th level, your Brand has become much more potent. The psychic damage dealt by your brand increases to twice your intelligence modifier (minimum of 2). Additionally, the branded target cannot take the dash action. If the target attempts to teleport away or into another plane of existence, it must make a Wisdom Saving throw. On a fail, the target takes 4d6 psychic damage and the spell fails, otherwise they take half damage.
Additionally, you gain access to an additional Blood Curse
Master of Blood
Upon reaching this level, you have become a master over your blood. Whenever you use an effect that would require a Hemocraft Die roll, you can roll it again and take either of the two rolls. Additionally, you gain advantage on any saving throws that would charm or frighten you.