Only really finished this in the sense that I've seen the game's ending, but there's so much more content that's hidden past that point that, for once, I actually feel like coming back to a game to try and 100% it immediately. It does a lot of similar things to other open-ended Metroidvania games but has its own striking atmosphere with beautiful pixel art. I also really enjoyed the unique abilities you unlock and how they affect the puzzles. How many other games make you collect and use a fucking Slinky as an important progression item?