I finished the game last night and even got the Platinum. It's not terribly hard to Platinum with only one missable trophy. There's 44 of these fascinating runes/stones that tell you stories/legends in Norse mythology. I almost missed one so I found a guide for the endgame ones as you can't always properly backtrack. Also, there's no chapter select, so you'd have to go through the game again, which honestly would take away from the experience.
The actor they got to narrate the stories does a fantastic job, and truly the audio work for this game is by far it's shining star. There are many other aspects that are excellent, but the audio carries you through the environment and makes those environments feel so oddly surreal. So if you're still unsure what to expect in this game, it really is only about 25% combat while the rest is exploring the landscape and trying to get past these obstacles that are almost assuredly all in Senua's head. I say almost because the game does a fine job of weaving actual physical world forces with that of the supernatural.
The only flaws might be that if you try to get the game done quickly, you're either going to miss the fine details of Senua's psychosis on the environment, or you're going to become unnerved with experiencing Senua's psychosis. She has moments where it seems she's beating or winning against The Darkness, but there's always something that brings it back and reveals more of what drives Senua's pain. Throughout the game, there will be varying forms of gameplay that represent the different experiences of failing mental health. To me it's a positive because of how inventive and dedicated Ninja Theory was to exploring mental health. However, the differing gameplay could annoy you because you personally have to adjust in-game to exploring the world in a new yet hampered method.
So there really isn't any permadeath, but there's a reason why the game states The Rot will consume Senua after many deaths. I won't spoil it, but death plays a very important role in this game. If you didn't bother reading online about it, you'd have more concern for Senua and what seeks to do her harm. Now the game isn't terribly difficult. I did die a few times though, but it wasn't until over halfway into the game when there are instant death mechanics based on fear and panic. For those that have played...
Thinking on it, I guess another flaw would be that later in the game, I felt almost deterred to explore the environment because of those potential death traps. As such, it became a little less intuitive to solve some of the puzzles. One that seems to get people online is the M rune door leading to one of the bosses. You have to stay in the light, but to solve the puzzle you need to knock down a bridge that's way down a dark pathway, a.k.a. potential death. Thing is, unless you had visited the other side where you can see the bridge and light a torch, you wouldn't know it was even there from the other side because of having no light.
But even with moments like those, I still highly recommend getting this game, especially because it's $30 and does so much for the medium as both an artform and method is educating those on mental health. Dan kinda spoiled a plot point, but there's a depth to this game I fear that reviewers have been missing because they're in such a rush to get through a game. The ending was slight confusing, but after some minutes it all clicked and I was stunned by how it all connected.
9 Runes outta 10!