Shockingly, this is one of the best expert puzzle games, and perhaps the most unique one out of them all. The thought patterns you'll employ here are unlike any other puzzle game I've played. The feeling of mastery is exceptionally potent, rivaling or exceeding the best puzzlers, even though under the hood all you're doing is nesting and un-nesting some functions in computer code, and pushing objects up or down a literal "stack" - but why is that?

This game's core concessions are also its biggest strengths. From the very start, you're playing with a triple-layered blindfold on:

The simple, logical, *binary* puzzle elements are abstracted into platformer objects like boxes, keys, chests, and level geometry, and strewn throughout a physical level you move around;
The room you're in is the only one on screen, other rooms exist only in your mind and you can't even see which chests go to what rooms, you must remember;
There is no undo or time rewind, one mistake, one wrong fold of the paper crane, one lost object, one accidental button press, one missed jump (!!) sends you to the reset button.

All this together creates an incredibly high-stakes experience where you untangle a vast knot purely in your own mind while interfacing with the silly-looking platform game on screen. Easy to play yourself, hard to watch people play and understand what in the world they are doing.

The base game is just the jumping off point - the expansion levelsets introduce a single mechanic each that vastly increase the complexity, and then there's the community-made DLC "The Ice Palace", which is one of the most sadistic levelsets created for any game. The limit is your own ability, and you can go to the stratosphere with this game.

11/10.