Quirk Creation Process
Context - ‘Why do you need it?’
What do you want them to achieve with this quirk?
Is there a specific character personality you want it to match with?
What type of career or hobby do you want to apply this quirk to?
Does it run in the family?
Type - ‘What is it?’
Emitter, Transformation, or Mutant?
What is its range (contact, close, medium, long, target-based, specific distance, varies, or none)?
Physical or Mental?
Active or Passive?
What does it to relate to (elements, sound, animals, etc.)?
Details - ‘How does it work?’
How does this quirk work (i.e. Bakugo’s explosions are caused by sweat)?
What requirements must be met for this quirk to function?
What happens when normal requirements are no longer possible (i.e. Uraraka loses a finger)?
Are there situations in which this quirk can be nullified by another?
What are its physical limitations (i.e. distance, weight, force, etc.)?
What are the potential drawbacks to using it (i.e. Kaminari short-circuiting his brain)?
Who will this quirk affect (i.e. self, others, both)?
If I don’t have any idea about what quirk I want to create, then I’ll start by asking myself these types of questions. It’s all about finding a foundation and using building blocks. You start at the bottom and step-by-step decide what you want until it all comes together into a rough idea, and then you just polish it off by figuring out the details.
To use my muses as examples:
Hanami - I knew I wanted her to have a non-offensive, passive quirk. Then I decided it should be plant based, and from there it slowly transitioned to Photosynthesis.
Ayane - She was easier to start since I established her to be Present Mic’s cousin, so a sound related quirk was inevitable, and I wanted it to be useful for rescue missions. Thus I ended up with Visual Sound.
Toko - This little rascal needed something to match his fiery personality, and I wanted him to cause accidental fires a lot. Admittedly, I think I had just seen a picture of the Pokemon ponyta, and that’s where I got the idea for Spinal Fire.
As for naming your quirk, just think of the most obvious thing you can. While I love symbolism and metaphors, quirks are named by a government body so that they can immediately know what they’re dealing with.