Background: In Chinese novels, at desperate time, characters would use a life saving technique, ultimate move, or something over their limits. But using that technique put a debuff on the character whenever it is a lost of cultivation, at time crippling, damage to meridian, et cetera. Also in Japan's novels, where protagonist would over spend their mana and the side effects may be dizzy or collapse. Like the slime anime, the slime would collapse for weeks after naming. Questions: To add on, my question is what are the side effects of overusing/overspending mana? What are the syndrome of casting that ultimate skill (like meteor), or using that secret escaping technique, or consuming that item / using secret technique that boast your fighting ability? Please, give me ideas/suggestions on the side effects that you can think of for using it.
From different novels it has been characterized as spending your life force in place of mana. Depending on the system the author is working under, life force can be anything from health points to the characters very soul. It's a toss up whether the damage incurred in this manor can be healed by magic, or if it must be healed naturally.
depends on what they're drawing from, but signs of aging (not like actually growing older, i.e. a 10 YO aging up to 19, but graying hair, wrinkles, and loss of bone/muscle mass) seem to be the norm. lethargy or passing out for minor infractions, mental corrosion if a great amount of focus is required (sanity, accuracy, selfdestruction, etc), or a rejection by the "natural" or "living" energies of the world could also work.
In Japanese novels, and most western fantasy, mana is like a way to measure your mental ''strenght'' that you use to bend the world to your will (use maggic), so overspending there would basically be the same as overspending your mental capacity, so side effects would obviously be stuff like tiredness, headaches, and in extreme cases maybe even a coma or brain damage. In Chinese novels, it's a bit different, and stuff like ultimate techniques often get their power from the caster spending their blood, lifeforce, lifespan and stuff like that. So the side effect of that would obviously be more physical, and directly life threatening, like your body being weakened (maybe permanently), your lifespan shortening, or you just directly die.
I can think of different side effects from using up your life force, damaging your spirit, causing damage or contracting of your spirit/mana pathways, exhausting your regeneration, sudden fainting similar to blood loss, death, becoming crippled, coma, temporarily stopping usage, damaging your mana/spirit core, outer energy poisoning, decrease in energy purity, weakening control or connection to mana or spirits, rapid aging, etc.
Given that the character is trying to act as a conduit for a far greater amount of energy than he is normally capable of " frying " is inevitable be it mentally or physically. That is to say permanent difficulties with handling mana, or becoming unable to recover to a point needed to use it ever again up to accidentally immolating oneself completely in whatever part you decide the character used to channel all the mana through. Edit: And as I typed it out, everyone already said it all clearly.
I imagine your body breaking apart from the inside since I imagine that for the magic to work you bring the mana into your body, refine it using arias and magic circles and then release it as magic So if you use too much magic, it'd be like taking the amount of water that flows in a river and places it into a small stream. The stream will widen drastically due to the water, which is not a good thing since in this case its the body that's being grounded and pulled apart by mana
Overuse of Mana can cause a variety of effects. These may include ringing in your ears. loss of hearing. extreme drowsiness. nervousness. fast breathing. confusion. seizures. Find out more about it on this scientific study https://www.MDS.com/effects-of-mana-deficiency-syndrom-1394728_947
There is a point to note though that some novels use the body’s breaking down as a method to strengthen the protagonist, much like muscle repair. For example, the widening of the mana channels or overuse could cause the maximum limit one can release or store mana to increase, and this can sometimes be used as a method for training to surpass one’s limits. Repeated usage of mana enlarges mana pool (often located in stomach area or heart), thus increasing one’s maximum mana. There are also those like decomposing and reconstructing the body in order to purify or compress the body more commonly found in CN novels, so after using said ultimate technique, the protagonist will suffer from weakness of strength for a short period of time before growing even stronger than he originally was. Reasons for not doing so anytime possible would be due to the unimaginable pain or consequences (i.e. permanent damage to life force) so it will only be used when need be.
Call it overused mana causing physically tired and sex hormones cant be released for weeks. Goodbye boner.
OR the person enters a berserk state, causing them to be unable to control themselves. Sometimes this is not a problem at all and the MC just lets loose. Other times he has to restrain himself in consideration of his comrades, often times females. Due to well, the unrestrained sense of reasoning and production of sex hormones. So quite the opposite of what’s been said here.
I think feeling weak/comatose after is fine, or if you wanna be cooler like what Tristan said above, maybe overusing your mana makes you unable to control the flow/intake of mana, causing you to go berserk, rampaging around.
It depends where Mana comes from, if you have say a mana core, overuse could lead to it cracking/fracturing causing your skills to be much weaker or your mana to be less proficient at restoration.
Not sure whether these count as side effect(s) or not: * no/out of control (Cultivation Chat Group): a senior put a charm on MC (it's a temporary tattoo) that got similar function to a flying sword, which would enable MC's to escape & fly directly to the senior's side when his life's in jeopardy + it can be activated both manually & automatically. Unfortunately once activated, MC's got no control whatsoever: - once, he ran over another cultivator, turning both of them into literally a screaming comet - another time, MC was sent to space for a month due to a bet w/ said senior above. The charm was modified so once the time was up, MC's would again fly to senior's side. Problem was, while in space, MC's got locked down on an area where time flow faster than outside. You could guess what happened next. (^^i) * white hair (Slayer TV series): apart from the usual mana deficiency tropes, at the end of the last episode (can't really remember whether it was 1st or 2nd, sorry), Lina's hair turned white after shooting her ultimate spell * can't remember where I read/watch, but there are spells/magic that fall as MAD type (Mutual Assured Destruction) where it was so powerful/destructive, the mana/SP consumption was also tremendous that it would simply took the caster's life force out as mana supplement (IOW, both the caster(s) & her/his/their target, die)