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Ask Me Anything About My Blood Based Magic System


(I figured that an AMA would be the best way for me to catch holes and address intricacies in my magic system, before I go nuts with it in my work in progress)

Within the World of Ethyes, the dominant sentient race are the Apsara. They are mostly human in appearance with three notable differences. They're hotter, age 1 year for every 3-5 years that we do after the age of 20, and they have miniature "stars" (Khei/Microcosm) in their eyes. In the middle of the "star", where the pupil should be, is a white "black hole" (Kheria/Core).

Anything that enters the eye's black hole becomes part of the Khei. This is mostly through the bloodstream, but there are rather gruesome ways around it. Once something is part of an Apsara's Khei, the Apsara can use the Khei's "starstuff" to regenerate a copy of the substance within the Khei and send it to any part of the bloodstream (mostly the fingertips). This can include window cleaner, alcohol, heroin, detergent, and powdered metals. But the Khei cannot generate energy, for that power belongs to the Mahoragas. The eyes (which can be blue, silver, gold, bronze, or red) glow during the generation process.

However, most things that get in the Khei will be destroyed unless it is coated with 'catalyst blood' prior to its entry into the body. Catalyst blood protects the fidelity of the substance in the bloodstream while neutralizing the most dangerous effects. Catalyst blood can also be used to safely coat and expel substances outside of the body. To create Catalyst Blood, an Apsara only has to process blood into their khei to convert it. However, the effects of Catalyst Blood only last for a minute and become Dhukka afterward. Dhukka cannot be expelled out the body through normal means, since can't separate itself from blood like Catalyst Blood. Dhukka can however be used to create more Catalyst Blood, but if Dhukka is left in the bloodstream for too long, it becomes Mara, a poison that slowly destroys the Khei.


Myth Weaver
My first question is almost always... How does this affect the story?
How do the Apsara and their magic affect the story you are telling?
Personally, my position on magic, if the mechanics are not essential to the story, is to keep it as loose and unexplained as I can. But I like "little" magics.

Almyrigan Hero

Honestly, my only recommendation is to simplify or just not overexplain it, and say "these glowy-eyed people can absorb and reproduce matter."

When the premise is "bleed on window cleaner, inject it into your bloodstream, scan the composition with your galaxy eyes, then shoot window cleaner from your fingers," it's... kind of hard to point out (or even ask about) any individual 'holes' in the logic. It's simply too foreign, both to real-world sense and to established myth.
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The magic system affects everyone in my story because it's tied to all Apsara's biology. Since my setting has an Apsara majority, it also affects some of the non-Apsara's as well.

Universal Examples:
- Spellbooks are the alternative to tablets and smartphones in the setting. Instead of face ID or password, most devices use catalyst blood input as an identifier. This is because spellbooks interact with khei or catalyst blood anyways through interactive spellbook pages such as those that do instant blood tests or use khei products to "3D print". Arsene, who is a mixed-race Apsara and Mahoraga* and cannot use either magic system due to hybrid disfunction, has to use a cheap lock and key spellbook that his government makes for out-of-space visitors. He already considers himself to be a perpetual foreigner to his country, and this doesn't make it any better.

- Medicine doesn't exist in the form of pills unless you're an alien or a Mahoraga. Akoso, who is an Apsara pharmacist, creates high-fidelity potions that contain medicines that can be continually catalyzed using Khei. If someone has a cold, they only have to flood their bloodstream with a Nyquil-like* substance once, can their body will generate the other doses. However, like memories, Khei schematics can be "forgotten over time", so people still have to visit the pharmacy again if they have another cold. For medicine for treating chronic illness, the Khei schematics last a long time but can accidentally, at anytime lose their "fidelity" and create a Khei with a different effect, and fixing that would take another potion dose.

-Khei is an A+ single-target weapon, but a terrible AOE weapon (Khei's firing style is literally finger guns). Though guns are banned in the setting, no one plans on using them for self-defense anyways, since its cheaper to use blood. There are several legal khei that are kill-on-contact poisons/nerve killers that can only be activated when there are high levels of cortisol(stress hormone) in the body. However, in war Apsara use khei primarily to create passive "buffs" (stimulants, painkilling, ect.) when handling conventional weapons. Baiyin, who is a sniper merc, uses her Khei to slow her perception of time and coats her bullets meant for high-value targets with a substance that makes their corpses deadly to touch.

-Accidental deaths caused by catalyst blood dissolving in the bloodstream before the substance is shot out the body happens all the time. The in-body lifespan of catalyst blood correlates with a person's physical fitness. Thus, PE classes for Apsaras are actually "magic" classes designed to improve their spellcasting capabilities.

*Mahoraga do have their own "catalyst blood" but it's used to deactivate energy instead of matter
*Yes, there are some Apsara who get addicted to cough medicine and do exactly what you think they would do.


Almyrigan Hero

Good feedback. I'll explain the magic system like you did in the first chapters and leave my plan to have my lemony narrator spectate a middle school Apsara biology class to later chapters.

What I was going for with this magic system was to make almost every character an eldrich horror to the actual eldrich horror narrator, who happens to be an alien anthropology grad student writing a comparative thesis on the magic systems of various humannoids. The narrator happens to be a blue fire-ball who dresses up in a suit, tie, and glasses to "blend-in" with said humanoids and can read minds up to a five kilometer radius. How you described the magic system is actually in character for the narrator, actually, but I suppose I still have to tone it down.