The player character is...
- Listen closely to Kates radio message played next to the lawn chair. The first phrase uttered, extraordinary, doesnt sound like it came from the radio, but in-person. Then the radio message officially starts.
- In the moments leading up to her forming with the light, The Pattern shows her the important events of the valley to her in a possible attempt to explain it's actions. Kate is the only character to seem to interact amicably with the pattern.
- Also, when you enter the sixth tower, you walk up to the table with the fallen stool on your left. When the scene fades back in, your view is from infront of the stool, with the Light Kate standing where you had been. It's possible for this to be a change to a third person perspective to properly show what was happening.
- Throughout the whole story, Kate was treated like an outsider, eventually locking herself up in the tower for pretty much the whole story. As a perspective character, she would know the least about the people by the time the game starts, much like the player.
- The story makes the most sense with Kate as the sole survivor, trying to make sense of the lives impacted by the Pattern, before her own eventual absorption. The conclusion is kind of telling that theres a match for each person. Hers just happened to be the Pattern itself, which is the only other story character around by the time the game begins.
- A final reason Kate makes the most sense is if the player character is an outsider, the military would have the place under lockdown. If the player character was a resident, the devs would have to include an entire sub plot of the pc coming to terms with the situation. Kate, on the other hand, understood the gist of what happened, and would require the least amount of wtf!?-style exposition.
- Another human from outside the village who escaped the Pattern
- A non-human coming upon this years in the future
- Considering the state of the village, which includes cigarettes still smoking in ash trays, it appears that the Rapture happened very recently. (But then again, time itself doesn't seem to make sense in this story; the sun moves dramatically many times, for no reason.)
- The Pattern itself, retracing its own steps and slowly coming to realize that it may have done something wrong. (This would explain why you have no visible arms or legs, though of course that's just an Acceptable Break from Reality in most games.)
- The spread of the pattern, as well as it's presence on the phone and it's achronal state, may mean that the reason why we find scenes and areas the way we do is that it is our first visit to the area- and the Pattern's. Why does the sound of the pattern appear during Stephen's telephone call? Because we picked up the phone. Why does the pattern spread through all the venues despite Stephen's best efforts? Because we, in our interpretation of events, have been following Stephen! Why is everyone sick and disappearing, despite some being far from ground zero? Because we've been hopping in and out of their lives to observe them... Jeremy and Stephen comment on our presence, just as we walk up to them as well.
- A Security Guard who works at the Observatory. However, the only implication that this is who we are playing as is the fact that we begin the game not only right outside the locked gate of the Observatory, but also the open Gatehouse where he would be working.
- Has taken all of humanity and much of the life on earth.
- Has seen all of humanity, but only taken the surrounding village, and most of earth is okay
- Has taken much of humanity, but not all of it, and humanity will rebuild itself eventually
The Pattern is...
- Part of a race that collects and preserves memories of sentient races, destroying them in the process, but does not know that its actions are harmful.
- A being created by God sent to rapture humans that was young and confused by humanity.
- A dying alien that survives by finding hosts
- The last of its kind, which is why it felt "lonely"
- Kate's "soulmate" and was attracted to this planet by her
- Alien Nanomachines, Creating The Singularity
The Pattern was mostly contained even after it escaped the valley, and you play an SCP Foundation agent investigating the disappearances.There's a reason no one's ever heard of this village... the SCP wiped it off the map to prevent people from investigating and becoming infected.
The Pattern was manipulating Stephen the whole time.
- Stephen tried to stop the Pattern, but he couldn't think straight because he was infected and the Pattern inside him subtly scrambled his thoughts. That's why we hear him using radio to communicate with the outside even after he realizes that the Pattern travels through radio waves. His efforts to stop the Pattern actually helped it to spread, but he didn't realize what he was doing.
- Alternately, he was fully aware that the Pattern might escape via his transmissions, but he figured it was worth the risk. The Pattern doesn't necessarily travel on all frequencies.
The Pattern has permanently messed up the flow of time.
- This is why the sun jumps around after you see a major scene.
Each "guiding light" is unique
- Each "guiding light" you follow around is actually one of the townspeople. The Pattern transformed them into these golden forms when they died, and now they're trying to tell their story to the player. Each chapter has a unique light, which is the "soul" of the person whom the chapter is named after.
- Lizzie is revealed to be pregnant. In Lizzie's chapter, the guiding light has a smaller light following it around. This small light is her unborn child.
Everybody outside the valley turned off their radios
- Near the end, Stephen says that he can't get any signals on his radio. He takes that as a sign that the pattern has consumed the whole world. But maybe everyone's fine, and he can't detect them because everybody followed his advice and turned off their radio equipment (by order of the government).
There is a secret seventh chapter
- The game has six chapters. The observatory has six towers. When Kate is trying to boost the Pattern's signal, she says "if I conceptualize the point of origin as a seventh tower, it just might work." The game is filled with radios which you can interact with to hear Kate speak. But before you interact, the radio is reciting a series of numbers. Each radio is reciting a different series. After you finish Kate's chapter and reach the credits, there's a long series of numbers at the end of the credits. So here's my speculation: Somehow, we're supposed to decode all these numbers and uncover a message. The message will tell us about a secret in-game action we can take which will unlock the seventh chapter. The name of the chapter will be "The Pattern", and it will solve at least some of the mysteries.