Quirks are a supernatural ability that resulted from a biological evolution. All Quirks come with an underlying Atlas Quirk, which grants Quirk wielders the required secondary superpowers they need in order to function without harming their users, this Atlas Quirk allows for the possibility of superpower possibilities through training alone. Shōta Aizawa is a grand example of this, fighting on par with other heroes and villains without a quirk that increases his physical capabilities. Quirks are unique to the individual and are presented in one of three ways. You are able to select any single quirk that is not One for All or All for One. This can instead be left up to chance if you wish.
Emitter Quirks: Emitter Quirks allow individuals to generate, control, and/or release certain substances or energies. Emitter Quirks make up the majority of Quirks, leading to a wide variety of properties and abilities.
Transformation Quirks: Transformation Quirks alter the user's physical appearance or grant them special features. This can include turning into an animal, growing extra limbs, or changing body parts. Transformation Quirks generally require a certain level of focus in order to activate them, preventing accidental activation.Transformation-type Quirks are the only known type of Quirk that can bestow the user attributes they do not normally exhibit by default.
Mutant Quirks / Heteromorphic Quirks: Mutant Quirks cause a permanent abnormality to the user's body that is directly related to the power or enhancement. Mutant Quirks cannot be turned off, as they are permanently active, this allows them to be far more resistant to quirk nullification.