Ether One

There is another version of the game called the Redux version. A remaster of sorts. I do not see it here on Steam anymore but that's what I played. Perhaps you get it when you buy this one. Anyway, you can't review that game separately since this is the only one in the store so I installed it for a few mins to be able to review the game.
The game is mostly an open world (actually large open maps with occasional loading screens) sandbox puzzle game. The music is relaxing/calming and the environment is very serene but also quite surreal. There is little to no hand holding. You could walk around for hours trying to understand what to do and why to do it. Some puzzles are easy and many I needed a guide for. The inventory system is half annoying and half clever. On one hand, you can 'teleport' to a room with tons of shelves to put stuff but you can only ever carry 1 single item at a time. So yeah, you'll be doing lots of teleporting. There are hundreds of random items here and there and most are unimportant so you can never be sure what to grab and store in your shelves. Basically, if most modern games do entirely TOO MUCH hand holding, this one doesn't do enough.
With that said, no matter what, do NOT give up on this game. If you start getting lost and impatient, just use a guide to help you. When you finally get to the end and understand what in the world is going on, the ending makes it all worth it.