So, I picked this up. Played through all the tutorial puzzles, and was like "wow this game is awesome, though the puzzles don't seem like they can get THAT hard".
Now gotten up to about the fourth or fifth area and have been stuck on single puzzles for 30+ minutes at times. Bloody hell, this game gets crazy difficult and I kind of love it because the puzzles feel so satisfying when you finish them. The solutions are often pretty simple in many ways as well but require you to really understand the game mechanics and rules. Like "Broken Playground" was a really creative puzzle to solve.
I'm currently stuck on one of the bonus puzzles in I think the 2nd section. Small Pond or something it was called. I'm sure there's a creative answer here but damn, I just can't make that Win block into a rule. I'm pretty sure if I could turn all of Baba, Flag and Key into the same thing (any of the three, they're interchangeable) I could solve the puzzle, but that doesn't seem possible without breaking the "is You" part of the rules...