Not sure if this would be categorized under plot development or research. Skip to the last paragraph if you don't want a rant on how a plot point in my story will work. I've put in bold the research part of my thread. In my fantasy novel(s) i am writing, a form of magic that is used by some people is blood magic, but maybe not in the traditional sense. Hopefully, the certain type of blood magic i am going to be using is quite literal. A skilled user of this magic and control their blood, and an even more powerful mage can control other people's blood. For example: A character in my story is able to magically displace the blood in her body to someplace else nearby, and using magic she can "teleport" to where her blood is now. For the most part, the blood moving is instantaneous, but if it were to travel a significant distance it would mean my character would be without any blood whatsoever for a decent amount of time. Another example is rapid healing; if my character were injured, she would be able to bring a large amount of blood to the wound in order to clot it faster, not exactly healing it, but stopping blood from pouring out of her body. Perhaps an even more advanced magician could control the blood in another persons body and therefore control their limbs. I am planning on having the drawback be loss of blood. The more magic used in a certain time, the more the effects are apparent. If my character were to repeatedly drain all the blood out of her body and put it back in, or repeatedly send most of her blood to a certain area, that would be bad. If a magician were to fall unconscious due to blood loss, their magic would stop working and the blood in their body would return to normal. The gist of it is being able to control the blood flow in their body, not just with blood vessels but magically as well. The real question is how long would a person be able to have no blood in their body. I assume no longer than 6-8 seconds (based on my knowledge of martial arts chokes) but can it vary, or would the body just instantly shut down if no blood were there. It's not like the blood will be gone forever; within a few seconds the blood in their body would return to normal. Temporary displacement of blood is probably the word i would use to describe it.
Well, I think that the immediate issue would be that there would be no blood to carry around oxygen anymore. People can survive without oxygen for something like 6 minutes without having permanent brain damage, so I think you're safe on that account. I have absolutely no idea what would happen if the body's fluid level suddenly dropped to zero, though . . . perhaps the person would pass out, as with severe dehydration?
Only the blood, which is magical for those certain people, is gone. Water and fluids stay, and even if they left they would return with the blood in a matter of seconds.
Did you google how fast someone dies after losing too much blood? Because it's not long. According to this article, if you lose 40% of your blood, your heart won't be able to maintain blood pressure, so organs would start to fail. So I think it's safe to say, if a magician took all of the blood out of their body, they'd die. Immediately.
Also, you have to clarify "all of it." Because blood contains a lot of stuff other than hemoglobin, and blood is often tied directly to lots of other bodily fluids.
The martial arts chokes sound like they're about how long you could survive with drastically reduced blood flow. But no blood at all would mean no pressure in all sorts of things that are accustomed to always always being under pressure. And then all those things would be very abruptly re-pressurized. I strongly suspect that a person couldn't survive that.
Yeah.. it'd be like deflating a lung. Lungs work because they always have air in them - puncture one and deflates like a balloon, which makes it really hard to breathe. Remove all the blood from your body, and your veins and arteries would collapse, your heart would implode, and your brain would probably shrivel up (it uses a huge amount of blood). In short... instant death.
Why not solve the problem this way ... We have red cells for oxygen transport White blood cells for our immune system maybe your magicians have "abracadabra" cells that let them do whatever. They send those cells out and then the body follows. ok .. it's a little close to the midichlorians that Star Wars used but who cares
Wouldn't it be better to have blood as like the source of power or something? This seems a bit specific, awkward and difficult to work. The key thing if you do do it is humans have a lot of blood. 30% which you could probably survive without for a period, is litres. Probably enough to do something with. It's like how human intestines could stretch across continents over the whole world. We be compact creatures.
The easiest solution to your issue? It's magic. Unless you want your magic system to operate under more scientifically fundamental logistics, just have a character puke up a quick explanation like "The caster's body is locked in a type of suspended animation, which can protect them from the immediate effects of the blood loss for so long", that way you could leave the story open to stuff like "John, the retard who doesn't know shit can only keep blood out of his body for several short moments, but Aralozolaozxox, lord of the seven hells, was fabled to be able to do it for as long as several weeks!". This way you could potentially leave yourself a little more 'breathing room' with the practical schematics of writing with something like this. That's just my general suggestion. Like, if you wanted it more rigid and sensible, your entire story would have to revolve around only being able to keep ALL THE BLOOD IN YOUR BODY out of yourself for only a few short seconds- which, if written incredibly smart, could be some very, very interesting things that lead to very cool and intense story instances; but could fare to be quite difficult to write and you might find yourself hitting corners or inconsistencies as you wrestle with the plot (or maybe not, I dunno). Of course the other issue with this is the science of just losing most of your body fluid. I admit that the reaches of my understanding in biology and human anatomy don't extend so far that I could answer that question at all, so maybe it's worth some research. You might end up having some people picking the story apart with criticisms like "if Bilbo Lannistar removed all the blood in his body, it would have made his body collapse in on itself" or something like that, so adding in some kind of exposition that a mage would lock themselves into some kind of 'frozen state' so that their body could safely have no fucking blood in it would help kind of clear up any potential nitpicking, if that might worry you at all. In the end, I personally see two solid ways to go with it. Way A: Mages lock themselves in some kind of suspended animation. This is the "magic" option of the two. It explains away any potential gripes with physiology or practical existence with 'because it's Harry Potter' and would allow you to, theoretically, leave the story open to having characters that can do this sort of extreme magic for days, weeks, years or even eons at a time because they're so versed or gifted at it. Way B: It would take intense physical training to be able to do it for longer periods of time. This is the "realistic" option of the two. Maybe characters can't do it for 100 years, but it would make the magic a lot more difficult and therefore impressive if it not only took years of hard book/scroll/whatever learning, but also required peak physical strength and endurance to endure. For instance, a novice may only be able to pull it off for as little as a few seconds whereas a master might be able to do it for a whole minute. Of course if you went down a more 'realistic' path, I would suggest doing a little research into the topic if you don't want people whining that "but dats not how the body works!!" down the road. Way C, I suppose, would be a combination of the two. Keeping it "realistic" but also leaving it open for characters to be beyond any realistic possibilities. That's just how I see it, at least.
I was kinda thinking the same thing: if it's possible, then the magic would enable a bloodcaster to do it without killing herself - otherwise, it wouldn't be very effective magic. Here's another idea: You said she could teleport to where her blood is. Does there have to be a specific amount of blood to enable this (i.e., does it have to be the entire volume of your body)? Maybe the distance you can teleport is related to how much blood is present at the new location - i.e., you could move a few feet to a few drops of blood, whereas a few liters could be a few hundred yards, or maybe even a mile, away. I'm wondering how she displaces the blood in the first place, but that's probably a topic for another discussion.
