Blood Mage (5e Subclass)
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Your innate magic comes directly from the power enclosed deep within your blood. This is the most powerful yet the most dangerous sorcerous origin. The use of blood magic generates an evil aura that obviously attracts demons of all kind. Because of that, most blood mages don’t live long or, if they do, they succumb to the temptations of demons. Blood magic has been banned everywhere and blood mages are even hunted down in some places. Blood mages are really rare and often considered abominations.
- Important Notice
This class uses hit points as a resource to cast spell and makes you lose the possibility to multiclass in any other class that can cast spells. Be sure that you really want to go down that road before doing so, as you will damage yourself as much as the enemy does. Plan accordingly. This class is only made to those who want a challenge and try a new mechanic. Also make sure that you Dungeon Master agrees with the choosing of this class before doing so.
- Blood Fuel
Starting when you choose this origin at 1st level, your hit dice are changed to d10 instead of d6. Your spells are fueled by your blood, making your hit points a resource to cast.
Casting a spell expends a spell slot of the corresponding level and costs a number of hit points equal to twice the slot level.
You can continue to cast spells when you no longer have spell slots, but doing so costs twice the required hit points. If you spend twice your number of spell slots for a given level, the hit points cost is now fourth times bigger.
For example, if a level 10 blood mage casts 4 1st level spells, he must spend 2 hit points per spell and goes down to 0 spell slots. If he casts 4 more 1st level spells, they now cost 4 hit points each and he goes down to -4 spell slots. From now on, all other casts of 1st level spells costs 8 hit points and still lowers the counter of spell slots. The counter of spell slots goes in the negative, which means using font of magic to regain spell slots only adds to this number; it does not directly bring the counter back to one.
Additionally, starting at 2nd level, you gain the metamagic Dry spell, which halves the hit points cost of a spell. Casting a Dry spell requires 2 sorcery points. You can apply more than one metamagic effect to a Dry spell. This metamagic does not count in the two you select at 2nd level.
Also, if you drop to 0 hit points from the cost of a spell, you are automatically stabilized.
When you choose this origin at 1st level, you lose the possibility to multiclass in any other spellcasting class.
- Blood Bending
Staring at 1st level, you can control the blood that flows out of your body, making it possible to use it to block or deflect attacks or to magically lash at an enemy. As a bonus action, you can start to blood bend. Doing so costs 1d6 hit points per round and lets you decide to use it in its defensive or offensive states. In the rounds that follow, you can change its state with a bonus action. If you haven’t started to blood bend in a fight and you get hit by a piercing or slashing attack, you can start to blood bend in defensive state as a reaction. If your new armor class would have blocked the triggering attack, you only take half damage from the triggering attack.
If used in combination with a cantrip spell, the hit point cost to maintain the blood bend is increased by another 1d6 hit points for that round.
The offensive state lets you (at the cost of an action) lash out at an enemy using your spell attack modifier for 1d12 + charisma modifier slashing damage. It has a range of 30 ft. The damage increases by 1d12 when you reach 5th level (2d12), 11th level (3d12) and 17th level (4d12).
The defensive state lets you add your charisma modifier to your AC. It also completely negates the projectiles from the spell magic missiles.
- Blood Siphon
Starting at 6th level, when you are in within 5 ft of a creature, you can try to siphon their blood to restore you. The creature must make a constitution saving throw against your spell DC. If the creature has received piercing or slashing damage in the last three rounds and hasn’t been healed after receiving it, it has disadvantage; otherwise, it has advantage. An incapacitated creature automatically fails its saving throw. On a failed saving throw, the creature takes 2d12 + charisma modifier hit points in damage and you heal yourself for half the damage inflicted. The damage increases by 1d12 when you reach 11th level (3d12) and 17th level (4d12).
If the creature is willing to be siphoned, it can choose to fail the saving throw and you’re healed for the total damage inflicted. Additionally, if you are within 5 ft of an incapacitated or willing creature, you can use its blood to cast your spell as a bonus action. The creature you siphoned must have blood for it to work. You may use this feature a number of times equal to your Constitution + charisma modifier (a minimum of once). You regain all expended uses, when you finish a long rest.
- Bloodied spell
Starting at 14th level, you can empower a spell by shedding more blood. When you cast a spell you can choose to maximize its damage OR to impose a disadvantage on the saving throw against it. Doing so costs you five times the normal spellcasting cost. The five times cost stacks with the cost multiplier when casting your higher level spells. For example, a level 14 blood mage casts a Bloodied Delayed blast fireball, the normal spell cost of a level 7 spell is 7 hit points, but since it is the highest level a level 14th blood mage can cast, the spell cost is 3 times 7, which means it is 21 hit points. And now, since it is bloodied, it would be 21 multiplied by 5 which mean 105 hit points to cast. The blood mage has to think carefully about it before making a spell bloodied.
Additionally, if the blood mage casts a spell in last resort, and the cost of the spell brings him to 0 hit points, the spell is automatically bloodied.
- Blood Rush
Starting at 18th level, whenever you are under a third of your maximum hit points, you can use your metamagic without spending sorcery points and spell costs are divided by 3.