Rhem 2: The Cave

The Good
It was definitely very atmospheric. I had this game as a kid and playing it now gives me mad nostalgia vibes. There is a strong steampunk streak in the game, which is slightly similar to Myst but also very unique and unlike any other game I have played. I have fond memories of sniffing around in the elevators early on in the game and playing with the temperature gauge. It is definitely anything but forgettable, like many of the games I enjoy it has an ambience of loneliness, sparseness and an almost unsettling tone (especially when it becomes clear you're not truly alone in the cave). Definitely would recommend.

The Bad
The game is absolutely impossible for anyone under a 250 IQ unless you have a walkthrough. You will be checking the walkthrough constantly for almost every puzzle. It has only been through recent replay that I have even managed to get about halfway through and even with a walkthrough it's really damn difficult. I can pretty much speedrun the original Myst and Riven in an afternoon at this point (although a lot of that is memory, admittedly), but Rhem II is a whole different kettle of fish. I refuse to believe anyone has solved this game on their own.

The Bottom Line
It's definitely worth checking out. Especially since, like the first Rhem (which I never played), the entire game was pretty much developed by one dude (Knut Muller, from Germany). It's actually pretty impressive when you consider that this is all one man's work. Even Cyan (whose game Myst is the most likely comparison to Rhem) had a team, albeit a small one, working on their games. And yes, I am aware that Muller didn't LITERALLY do it all himself, but he did almost everything. Just make sure that you have detailed notes of the solutions to all the puzzles, and be prepared to do some heavy duty math (no joke, there is literally a puzzle which involves complex algebra pretty early in the game). Also, don't think too hard about the plot since it has almost nothing to do with the actual gameplay --- not that that's a problem.