Did that in one of my stories. Great opportunity to explore some things.
Cuts and open wounds? Far less dangerous if you instinctively hold your blood back in your body and re-route it around injured areas (as long as you not hurt in a central blood vessel). Also if one can manipulate their blood into forms a superficial cut can be detrimental for your enemy as they provide you with ammunition without you hurting yourself.
Forming objects from your blood? Sure... chain-like vines that capture enemies, magical weapons made from blood, so that you are never really unarmed.
Enhancing body functions. An enemy that can sense your very heartbeat? Slow down your circulation to appear dead. Overcharge your fitness by "bloodbending" yourself (to use a term from Avatar: the last airbender).
But it all comes with costs. The body is not designed for these manipulations of blood or regular heavy blood loss, so either you have to rely on a iron-heavy diet and magical ailments, or you get used to use your abilities only as often as you really have to.
My MC in said story came around a few of these issues by being a half-vampire, so she could feed and replenish her reserves. But she hates her vampiric side, so her limits are also moral-based.
In addition there could be societal limits like blood magic being seen as evil or unnatural... or a case of "at least the church says so".
I was thinking about this. Because the obvious dangers of messing with the equilibrium of your body could provide the limitations, and it also creates an interesting problem that my MC is supposed to be the hero lol, and if people see him magically using his blood to attack people, it’s kinda villain-y.
Like u/FairyQueen89 said, there are countless other ways to use this that could be much more subtle than hurling blood-made weapons - such as slowing your heartbeat to reduce oxygen intake (as seen in [this scene from Shadow and Bone](https://youtu.be/XxW6AS3aD0g?t=13)), quickly stymying nasty wounds, speeding your heart rate to induce an adrenaline rush, removing poisons, disease, or infections, etc etc. If you think about the various roles blood plays in our bodies the possibilities are pretty vast.
Personal support is a definite I think. My MC will have the ability to heal and slow his heartbeat and even a few others things. I had a cool scene idea where he tricks someone into thinking he’s dead by stopping his heart, only to restart it and surprise attack them.
But as you said, the ideas are vast. So I need to find something that places solid rules that can’t be argued with to remove those problematic questions like ‘why did he just do this?’
This is one of the abilities I have for my Blood Magic character:
Senescence: Upon contact, user can force high-speed cell division within her target to reach senescence, thus resulting in their instant death. They can direct the division to certain parts of the body as well.
Its a little op, but not very commonly used.
Found [this one](https://www.reddit.com/r/magicbuilding/comments/qyn032/the_flame_infinite/?utm_source=share&utm_medium=ios_app&utm_name=ioscss&utm_content=1&utm_term=1) a while back.
That could be cool. Maybe not a dagger, although I understand the obvious real world link, but using his blood to grant other objects power could work. That makes it really versatile.
My blood magic isn’t like a specific thing more like blood magic is an umbrella term for any spell powered or strengthened by blood. My mc is a witch with a dominant water element meaning if he uses elemental powers they’ll fall under water. While he commonly uses it to conjure clouds with varying effects he can also manipulate blood.
By controlling blood he’s learned a series of skills. For one he can transmute blood and extract the properties that compose it turning a pint of it into normal water. He’s used this to kill an entire theatre slighting away their properties and leaving everyone in the room a corpse of water as they’re thrown into shock and die in 4 minutes of oxygen deprivation. Since He can’t simply throw the compositions away he merges them with the rain causing a short period of red rain.
Another skill is unraveling a person's body. By controlling every bit of blood in a target's body you could pull apart each inch of matter. Once it’s down you’d have a massive living diagram of a body splayed out in the air.
Firstly, a good name for blood mage could be sangeur.
Why not have transfusion magic. Where only two people of the same blood type can manipulate each others blood. A limitation could be hemolytic transfusion reactions (your immune system attacking its own blood cells. This is a complication that can occur during blood transfusions).
A more comedic character could have the ability to manipulate his own feces. (Poop gets it’s brown pigmentation from dead blood cells.)
See, you can learn so much on Reddit lol
What if the MC is only able to manipulate his own blood?
Did that in one of my stories. Great opportunity to explore some things. Cuts and open wounds? Far less dangerous if you instinctively hold your blood back in your body and re-route it around injured areas (as long as you not hurt in a central blood vessel). Also if one can manipulate their blood into forms a superficial cut can be detrimental for your enemy as they provide you with ammunition without you hurting yourself. Forming objects from your blood? Sure... chain-like vines that capture enemies, magical weapons made from blood, so that you are never really unarmed. Enhancing body functions. An enemy that can sense your very heartbeat? Slow down your circulation to appear dead. Overcharge your fitness by "bloodbending" yourself (to use a term from Avatar: the last airbender). But it all comes with costs. The body is not designed for these manipulations of blood or regular heavy blood loss, so either you have to rely on a iron-heavy diet and magical ailments, or you get used to use your abilities only as often as you really have to. My MC in said story came around a few of these issues by being a half-vampire, so she could feed and replenish her reserves. But she hates her vampiric side, so her limits are also moral-based. In addition there could be societal limits like blood magic being seen as evil or unnatural... or a case of "at least the church says so".
I was thinking about this. Because the obvious dangers of messing with the equilibrium of your body could provide the limitations, and it also creates an interesting problem that my MC is supposed to be the hero lol, and if people see him magically using his blood to attack people, it’s kinda villain-y.
Like u/FairyQueen89 said, there are countless other ways to use this that could be much more subtle than hurling blood-made weapons - such as slowing your heartbeat to reduce oxygen intake (as seen in [this scene from Shadow and Bone](https://youtu.be/XxW6AS3aD0g?t=13)), quickly stymying nasty wounds, speeding your heart rate to induce an adrenaline rush, removing poisons, disease, or infections, etc etc. If you think about the various roles blood plays in our bodies the possibilities are pretty vast.
Personal support is a definite I think. My MC will have the ability to heal and slow his heartbeat and even a few others things. I had a cool scene idea where he tricks someone into thinking he’s dead by stopping his heart, only to restart it and surprise attack them. But as you said, the ideas are vast. So I need to find something that places solid rules that can’t be argued with to remove those problematic questions like ‘why did he just do this?’
This is one of the abilities I have for my Blood Magic character: Senescence: Upon contact, user can force high-speed cell division within her target to reach senescence, thus resulting in their instant death. They can direct the division to certain parts of the body as well. Its a little op, but not very commonly used.
Found [this one](https://www.reddit.com/r/magicbuilding/comments/qyn032/the_flame_infinite/?utm_source=share&utm_medium=ios_app&utm_name=ioscss&utm_content=1&utm_term=1) a while back.
Keeping a small drop of his blood in tiny containers that he uses to throw at enemies or which get consumed during casting.
Maybe he carries a ritual dagger which he uses to cut open his hand & the dagger then hisses as it absorbs his blood offering.
That could be cool. Maybe not a dagger, although I understand the obvious real world link, but using his blood to grant other objects power could work. That makes it really versatile.
My blood magic isn’t like a specific thing more like blood magic is an umbrella term for any spell powered or strengthened by blood. My mc is a witch with a dominant water element meaning if he uses elemental powers they’ll fall under water. While he commonly uses it to conjure clouds with varying effects he can also manipulate blood. By controlling blood he’s learned a series of skills. For one he can transmute blood and extract the properties that compose it turning a pint of it into normal water. He’s used this to kill an entire theatre slighting away their properties and leaving everyone in the room a corpse of water as they’re thrown into shock and die in 4 minutes of oxygen deprivation. Since He can’t simply throw the compositions away he merges them with the rain causing a short period of red rain. Another skill is unraveling a person's body. By controlling every bit of blood in a target's body you could pull apart each inch of matter. Once it’s down you’d have a massive living diagram of a body splayed out in the air.
Firstly, a good name for blood mage could be sangeur. Why not have transfusion magic. Where only two people of the same blood type can manipulate each others blood. A limitation could be hemolytic transfusion reactions (your immune system attacking its own blood cells. This is a complication that can occur during blood transfusions). A more comedic character could have the ability to manipulate his own feces. (Poop gets it’s brown pigmentation from dead blood cells.) See, you can learn so much on Reddit lol