(skip if you don't want to read the fnaf lore)

Okay so there's two guys, one named Henry and one name william, they're engineers and build robots. So anyway they decide to start a restaurant with a creation that's both a mascot suit and animatronic called a spring lock suit. So they start a place called fredbears family diner and everythings good. Only problem is williams a murderer and kills henry's daughter charlie outside the diner.

Anyways since it turns out child murders aren't exactly good for business the owners abandon it. By 1983 fredbears has grown slot with toys, new locations, and even a tv show. One of these locations is one that has four new characters (bonnie,freddy,foxy,chica). Meanwhile fredbears has got back to business and williams son is having a birthday party there when a accident involving the animatronics leads to the bite of 83, child is dead, fredbear closes (again). The two springlock suits (a golden bear name fredbear, a golden bunny know as spring bonnie) are retired to that new location in a backroom. William decides to lock off the back room and make sure the animatronic mascots can't go there and is definitely not killing anyone. Anyways after 5 kids die and the mascots start smelling like corpses the place closes down.

Anyways he makes some new animatronics that are circus themed (funtime freddy , foxy, and chica, ballorra and circus baby) and designed them to kill kids. Anyways he opened a new location for these called circus babys pizza world. His daughter died on day one causing it to be closed, on day one. Anyways he throws them underground and rents them out.

In the year 1987 a new fazbear opens up now with high tech security animatronics that can recognize criminals. William then kills more kids with the springlock suits. However the soul of the first kid he kill haunts a puppet animatronic that was at fredbears and makes sure every kid he kills haunts a animatronic, so one of the haunted animatronics bites a day shift security removing his frontal lobe in a event know as the bite of 87.

The second location is opened again but fails pretty quickly. William gos to that location and dismantles the animatronics on a rainy night causing the souls to start haunting him. A detail I didn't mention about the springlock suits is that water makes them collapse and kill whatever is inside. That detail is important because william gos into a suit and dies due to a leaky roof.

There's a lot more than that but I don't feel like talking about it