I'm struggling to write about this in my novel because although I've read plenty of cultivation/wuxia/xianxia novels, I've only been enjoying them as a reader would do so I didn't really observe or read properly about it because at that time, I wasn't aiming in becoming an author or even planning to write a novel. Currently, I'm writing a novel where there's cultivation in the modern world, but it's barely mentioned since I'm not yet writing the plot where a lot of cultivation and stuff would be mentioned. I haven't yet written how my MC is even using her Qi in some situations, but I have to write about it soon and I'm worried I might exaggerate and make Qi something overpowered or I might even underestimate it due to my lack of knowledge. I want to know what and how can Qi be used for, like using their Qi in strengthening their bodies in terms of power and agility, or maybe using their Qi for strengthening their objects wherein even a leaf can become a sharp weapon. I'm hoping for your answers.
Qi is basically Mana. It can do anything the author wants it to do. Most of the time it's used to nourish the body through some techniques, or as a fuel to use some techniques, or to cultivate to get stronger soul/mind/whatever.
As above, Qi is basically Mana. The only difference is that it's moved around as elemental juice more often than actual elemental effects. If you're trying to think of ways to use it, I guess a good shorthand is "I can do X by putting bits of my soul in Y." Qi isn't actually your soul, but assuming you've read non-Qi related fantasy that's what it sounds like.
If you are the Author, Qi is whatever you want it to be, just like GFLiZy mentioned. In my opinion you should see Qi like a ernergy system. Like a charging the human with energy to help him unleashing whatever he wants. Qi seems to be for most Author's like a atributless energy and through some kind of circumstance get a atribut. Imagine there some Envirmental changes, plants that change Qi to a certen type, or a cultivaten technic or even artefacts. Qi for a cultivator seems to be a source that he needs to refine to be his ,ready to be used, energy. The vitality boost from Qi seems to be there type of "overcomming there current limits" and as a new human they have better stats. I would refere ther to Pokemon or Digimon, if they evolve they get bette. By the way, there are a lot of "energy systems/forces", like life energy/force in years, soulsforce as a type to carry things with you even after death and getting memorys removed, any kind of element energy.
Qi is a concept in Chinese traditional medicine that means "energy" for short or "microscopic matters are very active inside the body that maintain and regulate the body's metabolism, maintain the vital activities of the body". If you want to describe "Qi" more correctly, you can read some Chinese traditional medicine documents and novels of Jin Yong, Gu Long, or other famous writers in the wuxia genre to know more about it. Nowadays, Chinese authors still borrow those authors' wuxia elements to write their wuxia/xianxia works. You can make your "Qi" too.
The problem is not what it can do, because qi/mana/supernatural-energy can do anything, thats the whole point of it When making a story, limits and costs are more important Effects related to the person´s body can usually be achieved with the user´s own energy Effects increase in cost if they affect other people, if they affect the environment or if they cause effects for a long in time, the higher the factor the bigger the cost Begin by making hard limits that cannot be broken, then once you have delimited the bigger impacts of those limits, move onto the soft limits, the stuff that can be overcome with technique, practice and determination Example: Hard limit: people can only use magic by absorbing energy from a non-magical source This means people can transform fuel and electricity into magic, energy sources and costs are very important to the populace Soft limits: an experienced mage can absorb grater amounts of energy from the same energy source, like obtaining two magic units from a bonfire while a regular mage can obtain one Soft limits: a mage can use a little magic to create a fire, then absorb a great magic from that fire Other example Hard limits: people have five empty energy spots on their bodies, and need to absorb the spirit of a monster to fill a spot, every spirit provides one natural ability, but they can exchange them later on Soft limits: people can use items to transform or supplement the abilities obtained from the spirits, like using a face mask to concentrate the power of a fire breathing ability They can also learn spells or techniques the regular way, those abilities are slower and weaker, but provide versatility Learning a spell or technique can also be a training for the day they finally obtain a specific ability from a spirit Other example Hard limits: people can be resurrected, but it requires a million sacrifices, and for the death to have happened one day ago at most Soft limits: healing magic can be empowered by sacrificing people, and some forms of healing allow to store health for later on, which is much cheaper than resurrection Everything can be done with "energy," as long as the cost and the method are consistent
Gas or air technically. Which is why their words for "panting" is "Circulating Qi". And suffocating is "Unable to circulate Qi". (For the ones who know Chinese it's, Cuan3 Qi4 and Cuan3 Bu4 Guo4 Qi4 that I was thinking of). It's anything you want it to be, like what the others said. It can be inert in the body from food or absorbing from environment, or it can be floating around in the environment itself. It could also be condensed into special objects like the cultivation world's version of oil (many stories use "Qi crystals" as hard currency). You can use it for literally anything, from health to raising the dead to communications all the way up to and not limited to planet destroying beams like the Death Star laser. Hell, many Wuxia protags are even more destructive than the Death Star. You don't need to worry about making Qi overpowered, you can't beat some of the really ridiculous things Chinese authors do with it. Your biggest worry should be making it so overpowered that the story becomes boring, not what it can't do. A sword you can see from planetary orbit anyone? lol.
Anything. a plot device if you need it to be. If you want QI to actually have... well. "Weight". it would be best to make different types of QI. A suggestion if you want it. The QI -> QI system Qi being formless energy that (Through training) can be converted to different types of QI. Formless QI can be used for body reinforcement, allowing the user to harden their skin and increasing the weight of their strikes Life QI can be used to heal Death QI can harm the soul of the enemy Elemental QI for elemental attacks!
Just think of qi as energy and what ever energy of any kind can do qi can but better For example when your body is growing energy is used to strengthen your body bones,organs and muscels ,etc with qi you can substitute the energy that would be used to strengthen your body natrally with qi witch would strengten your body faster as well saving the energy that your body would use for that purpose for somthing else . Another example would be when cutting somthing they that works is offten by concentrating the Kinetic that you put in into a fine point which would offer less resistence , with qi you can concentrate much more energy into a much finer point thus leading an easier time cutting and even finer cuts of harder susbstances. Another one is for electricity if i’m remember right electricty is mostly about the exchange of electrons between different atoms same as cells with most of the wasted energy between them going on to produce the byproduct/“waste” product of that exchange in the form of electricity’s so with qi and it’s versitlity it can go through this process far more efficiently then would other wise be fessable to create more electricity. This would also for fire and ice as well as qi would would only have to vibrate more or less depending which one you would want Also mind control abilities can be explained be explained as either a.) advanced hypnosis using the qi to rapidly provide stimulus or b.) actively controling some of the energy of the person or thing them selves. Furthermore having qi explained this way would also explain the strange creatures filling qi worlds as with the extra energy of qi flora and fauna would be able to grow both bigger and denser than on earth as they would have a more efficent source of energy much like how on average carnivores have much bigger brains then there herbivore counterparts on average . It also explain alot of the weird abilities as alot of the weird abilitys as there mostly the abilities of creatures of earth taken to the extremes. And types of energy would differnt types of property's and effects.