There's this thing about magic rats that brainwash society into being obsessed with rats and technology. Like, they infect one part of the world and suddenly everyone in the country talks about nothing else. You can't kill them either, and they are immune to all kinds of damage, except other rats. That means you can only make them slam into each other until they pass out. This makes them a great nuisance because you can't curb their spread effectively, and you can't get them out of your living spaces either because you can only carry six of them at once. So if you have two rats to use as rat flails to knock out other rats, as they are immune to damage otherwise, that means if there is an infestation in your basement and you want to use your car to drive them away from your property, you can only carry four per trip. If you try to carry more than the maximum number of rats, they warp into your computer and become viruses that spread your bank information and download rat porn. Because of this, people have largely given up and accepted the magic rats as their overlords.
One strange result of this is that society at large has become hateful of their children. Whenever a couple is found to have had a child, the father is promptly abducted by a government van and never seen again, unless they have a high enough governmentally sanctioned position to be immune. The child is then placed under strict supervision by an agent, usually called a Professor, who observes their development. When the child reaches the age of 10, it is separated from their remaining guardian and banished into the wild. As the child has been systematically starved of affection, it craves the attention of its betters and compulsively collects things to fill the emotional void. Most of these things are just more magic rats because as I've established, they are everywhere. But some desperate people have made a twisted game of the situation where they invite a kid into their house to knock out all the rats inside in exchange for a "badge". Children are lead on to believe that once they collect all the badges, they will finally obtain love and adoration. Few make it through this process without losing their mind and turning feral. These broken individuals stand alone at roads and in caves and cast their vicious stares in one or more directions all day, to ensnare those children that have not yet succumbed. They're called "trainers" because they train their eyes on you without needing food or sleep. If a child is caught by a trainer's stare, the victim's innate desire to receive attention will not let them leave until a blood match commences. If you are subdued by a trainer, you become one yourself, a process known as "nugget bridging".
This barbaric society that hates and encourages the destruction of their progeny is largely why the population is dwindling. With no viable means of retaining ones offspring, it has become commonplace for towns to have a head count in the single digits. Soon humanity will die out and the rats will inherit their world, presumably to form tribalistic guilds and living in houses that look like their face. There will be an annoying bird too.
Bizarrely, this seething disdain for children and their intelligence continues into the real world. The company responsible has made a practice of releasing the same exact game, over and over again, for 9 times and probably more. And the scary thing is that it works. Perhaps the true evil was never in the magic rats, but in the heart of man.
Also, sometimes you take pictures of them, or throw apples at their heads until they fall into a hole.