For the purpose of my review, my experience is going to be purely on the story mode. For any critiques or comments I make on replayability, just remember I am talking about the story mode and not the Procedurally Generated mode which I found to be just okay.

Labyrinthine is an excellent game and a terrific load of fun with friends or even by yourself.
It is very scary in the first few chapters, with the actual maze being my absolute favourite for how creepy it is and how there is a very real sense of being lost, confused, and hunted. It is quite difficult but there are just enough unique little areas and activities scattered throughout the maze to give you somewhat of a break.

Another thing that caught my eye was the surprisingly good sound design with no excessive use of loud noises and an emphasis on just letting atmospheric sounds like rustling leaves or the wind carry the sense of unease. It really makes it so that you aren't distracted and the reality of the situation can set in and cause the horror to be more internal.

The Graphics are also quite good and appropriate to the mood the game is trying to set.

The Puzzles in the game are well thought out and honestly can be pretty tricky. I would say on average it took me and my friend at least 5 or 10 minutes per puzzle not counting the time it would take to get back if one of us died. Most of the puzzles aren't frustratingly hard but not so easy that it isn't rewarding when you figure them out.

Finally, I'll just quickly note that there is a vague story behind it all which I think could perhaps use a bit more emphasis but as it stands it works just fine as an extra interesting way to keep you invested in the maze. It is nothing to write home about but it is cryptic, a little spooky, and ultimately just helps remind you where you are and give you a reason to keep going.

Now for my main critique:
As the game goes on, however, I also notice that it does become somewhat repetitive with the sewer/crypts being the weakest area. Effectively that area becomes the corn maze but way too complicated and annoying without basically any areas that are carefully curated to continue the story set out.
In my opinion, the best fix for this would be to lower the size of the crypts and focus on making their quality better with more areas like the clown area in the corn maze or the overgrown greenhouse.
I played with 4 people and very rarely did I actually manage to find my friends. Just to put it in perspective; once we separated from each other at the beginning I didn't see any of my friends for at least 10 minutes while I was just wandering the crypts.
Whereas the first chapter was just complicated and confusing enough to be scary, The Crypt was complicated to the point where it just felt like a grind after a while with a struggle to just finish it and see if the next chapter would be better.

Now with all that said, I am leaving a positive review because I think that the game has so much potential, and even with what is there now you can have perhaps one of the best Multiplayer horror games on steam at least for the first chapter.

I also appreciate that the devs seem to be active and I encourage them to keep going knowing they have a good base but use the first chapter as their model and maybe take another look at the Crypts since they are the biggest detractor from the game at the moment. Just as long as the devs don't get burned out they have an excellent game here.

I highly recommend this game if you want a fun evening with friends in a game that is yet unfinished but shows great promise. You can probably stretch the gameplay to about 5 or 6 hours depending on how good you are with horror games and/or puzzles. I would say that the game is adequately priced for the state that it's in but only because the first chapter is very well done and because the Devs do seem passionate about their project. At the moment the game can mostly be summarized by the phrase "Diminishing returns". I am not so certain about the replayability of it but you could conceivably pick it up once every year to experience everything again, although it would not be the same as the first time you played.

If you are looking for a concrete number, I would give the game 7.5/10 and maybe update that once/if the game gets a good major update with the new chapter.