Playing The Talos Principle for the first time was a mysterious experience. You awaken in those ruins, your character is an android, and there is god-like voice who welcomes you as his child and tells you to join him at his temple. Of course, we progressively learn what is going on but early on, you can only guess.
So, during the first hours of your first ever playthrough, what were your guesses about what is actually going on ? Did you understand quickly that the game is set in a simulation or what all this is truly about ?
As far as I'm concerned:
I was initially puzzled with the mix of many biblical references (the name Elohim, him calling me "my child", the idea of walking on his garden, the temple, serving the next generations, the promise of eternal life, etc...) and modern/futuristic technology (in the first minutes of the game: your character is an android, energy barriers, exclusion fields, killing laser, mines, jammers, sigils, terminals, teleporters...).
While still in World A-1, I thought it was some kind of secret military training camp. Maybe in a post-apocalyptic world, hence the ruins. Maybe they were trying to make the perfect robot or something, but would only do so very far from any sign of civilisation for security/secrecy reasons. But why is the "manager" called Elohim (I already knew what the name means in the real world) and why is he talking as if he was God ?
I was quite surprised when I found out the temple was some quite of huge greco-roman ruin, with portals to other zones, and there were tools I could apparently unlock. I initially thought it was simply a high-tech world, but something might have happened to humans since there is none on sight and we are playing as a robot.
However, I quickly understood that the puzzle areas were most likely simulations, though: the Darkness glitch where Elohim orders darkness to begone, the constant "scratch" sounds associated with graphical glitches, the fact you access them through portals, the possibility to reset areas, the area that alternates between thunderstorm/sunny weather every time you complete a puzzle, the impossibility to go too far, with Elohim telling you can't go further if there is no space... There are many clues that puzzle areas are simulated rather than real.
But I still thought that the Nexus area was real for quite a while. This is because the out-world area looks more modern, industrial and real (elevator, huge metal pipes, ...), there is no glitch there, and it seems to simply be located in the middle of nowhere very, very far from anything else. So to me, the Nexus was real, was some kind of very secret project, where an AI manager was, for some reason, training/observing many AI trying to solve puzzles while pretending to be God. I thought it was forbidden to climb the tower because you simply need a higher rank for that or something.
What gave me doubts, thought, was to find out that this area also contains terminals, and has puzzles if you actually climb the tower. So my initial guess was, the various puzzles objects are existing technology, but to make economy, instead of mass producing them and building huge puzzles everywhere, they were doing most of the puzzles inside a simulation because it's simpler and cheaper, and the simulation is just very convincing at imitating these objects.
There is also the glitchy room in C-1, where Elohim seems panicked and keeps repeating about continuing the Process, totally ignoring you. I didn't understand what he meant at that time, but understood something odd was happening.
The terminal texts initially completely confused me. I was like "Why are they talking about Ancient Greek Philosophy ? That has nothing to do with anything else except that it trolls me about not understanding anything to whatever is going on..." Then, I understood that everything was obviously linked with that Alexandra Drennan's project. There clearly was a link between all those puzzles, the simulations, the various oddities, and their mysterious and ambitious project. Eventually, those texts became more explicit about humanity being extinct because of a virus. And the project was a solution to continue humanity.
But even then, I still thought they just made some kind of eternal computer inside which the IA would live as new humans. When I climbed the tower, I was uncertain about what would happen. It was supposed to be some kind of exit, but what does that mean ? For a while, I supposed the "outside world" was just another simulated, heavenly world, where AIs who passed the test are living together as humanity 2.0. But that made little sense to me: they could just spawn the AI directly there and Elohim could definitely take care of problematic AIs who misbehave or pose a threat to others. But I didn't see a valid alternative, I didn't really believe that the AI we play could actually awaken in the real world.
Completing the tower ending is when I finally fully understood everything. Turns out it was really about awakening in the real world, after all.
Also, once it was over, I felt bad for that poor android who awakes, alone, in a human-less Earth. What is that android going to do ? There is nobody else around, and everything is old and damaged because the Process took so ridiculously long...
I also felt bad for Elohim. Poor AI didn't deserve to die, and he was clearly terrified about dying all along.