Ascending and descending
You know, given the ubiquity of his work, I'm surprised there aren't more M. C. Escher inspired games in this world There are a few, like Monument Valley, Manifold Garden and Superliminal, amongst a handful of others, you just don't find them all that often in spite of how striking a sense of space is found in Escher's work. Escher's Dream is not, unfortunately, a game of its own, but it is a neat looking Portal 2 mod with some trippy levels in it.
The mod comes from one Jack Phoenix, the latest in a line of map mods they've made over the years across multiple Source-made games. What makes this mod unique (and potentially nauseating for those who aren't so good with this sort of thing) is its approach to level design. There are of course bits where there are stairs titled at angles impossible to walk on but the thing that's interesting about it all is the ways in which you are encouraged to bend the rule of gravity.
One level sort of seems to loop in on itself and you have to angle your portals in such a way where you fall back into the room you were just in. Another sees you using some green gel which shifts the axis of gravity allowing you to walk on walls, so to speak. It's a mod about repositioning yourself in whichever way the level dictates you to do so, and it's quite delightful! It should be noted that the whole mod is quite short, only three maps long, but it's worth a punt. I've shared a video above for a look at it in action, though it does spoil the whole thing, so maybe only take a glance.
Mostly it has me hankering for a couple of things. One is another full game inspired by Escher's works (seriously, someone hop on that and let me know when you do). The other is an expanded version of this mod. The original Portal 2 is such a short game so it's always a treat when someone rocks up with some custom made levels that add something fresh after all these years.