Animal Instinct is basically a fancy way of describing rising aggression contained in natural predators that hunt animals.
An animal instinct doubles the strength, reaction time and reflexes twice as much. While originally considered a birth-defect by scientists creating the first mobian infused with at first thought to be "too much of the animal counterpart", it has been widely accepted as something born into everyone, if they look deep enough on accident.
As soon as a predator enters into their aggressor-mode, it'll take them to harm someone (depending on how much is needed for the aggressor), until they calm down partially again.
Some mobians get executed, due to their aggression. If they have a known history of aggressive behaviour, they can be murdered in few american states and a small amount of countries (mostly located in Asia).
40% of prisons world-wide are mobians imprisoned for their instinct.
A majority of predators with this instinct, serve jailtime atleast once in their life, if their parents aren't careful enough to raise a child properly and in time.
Only gen-4 mobians have grown out of this phenomenon, while gen-2 and 3, struggle the most with it.
Due to that fact, gen-4s get disliked by the animal-instinctive mobians, since everyone basically worships that generation, but fail to see, that they're normal, like everyone else is. Only that group has ever looked past their "perfectness", to realise, they're nothing special and just a glorification of natural evolution.
On some mobians, there's tell-tale signs of this instinct, like them having carnivorous/long or sharp teeth, more narrow eyes, larger pupils for males, smaller irises for females and more naturally stronger/thicker limbs or a chubbier appearance.
Protestors for political campaigns, tend to bring up the fact, that this is discrimination, against a group of individuals who struggle with what they describe as "uncurable disease", so the stigma often gets brought up, by depending on what political spectrum they're on, either "you needn't call it a disease" or either "it IS a disease that needs to be cured IMMEDIATELY", depending on country and state, this political spectrum can work in- or against your favour, as insurance will either cover the costs, or you will.
As for the animal-instinctive individuals, they tend to stay in the middle of the argument, often criticizing both sides, for their sheer stupid and too-side-leaning arguments for one favour, instead of seeing both. They don't want it to be called a disease, but they do want treatment, if available and needed.
Only the higher- and middle-class can even afford the medication needed, to keep the affected parties at bay, with their problems, causing often lower-class criticizens to lash out more.