This is easily one of the best mystery/puzzle games ever made. The objective it presents you with is straightforward enough, but the more you play the more you uncover beneath the surface, and as you dig, the game just gets deeper and deeper and deeper, seemingly without end. The depth of the mysery of this game is unbelievable. Truly feels like being a detective uncovering a vast hidden treasure. It's very addicting and hard to stop playing, you always just want to see that little bit further.
The way the overarching puzzles and secrets are signposted and hinted is also very well done, allowing for players to find solutions in multiple ways and offering stronger hints the more you progress. The hints themselves are also often very clever involving wordplay and multiple meanings, which give you a real "AHA" feeling when you figure it out. There's some truly satisfying and amazing moments of epiphany where you finally hit on the solution to something that's been bothering you for ages.
I have only a few complaints. There are a couple of major things that it is very easy to overlook, and once you've overlooked them, there's nothing to point you back to them, which means you can go the whole game having missed important information. Nothing huge, just one or two things that I think could have been hinted at better. There is also one very, very lategame riddle which I felt crossed the line of vagueness into being absurd, which I had to look up the solution for and was annoyed by after learning what it actually means.
Probably my main complaint is that there was no final cutscene or ending for solving the final, ultimate puzzle which both surprised and disappointed me. And while there is another point which you could also consider the "true ending", the game still leaves most of its biggest plot questions unresolved. Perhaps it's meant to be debated and discussed outside the game, but it still left me feeling a bit "unfinished".
In the end this is a game that is more about the fun of solving riddles and uncovering secrets, rather than a plot or a narrative. And for that purpose, it is one of the deepest, richest and cleverest games I've ever played and I highly recommend it.
