This is the best ZZT horror game I've played, at once goofy and effectively unsettling. It's also one of the better adaptations of an anthology to a game that I've played in any medium.
Robert W. Chambers' The King in Yellow (1895) is a collection of Weird Stories, with a capital W. The best-known of these follow aesthetes and obsessives through the decadent future world of the 1920's, and (mostly) don't connect to each other in any straightforward way. Some don't even connect internally in any straightforward way.
I came in expecting TKiYB to broadly adapt the most famous story, "The Yellow Sign." What I got instead was an eerie combination of multiple stories from the anthology, plus ZZT. The game captures the oppressive claustrophobia of a city where everything feels significant and eyes could be everywhere.
TKiYB ably plays on the player's (or at least my) tendency to bump into every piece of ASCII detritus looking for interactions and obsessively solving quests. let's just say that ZZT protagonist behavior is unusually in character here. And it takes full advantage of the fact that ASCII characters are by nature abstract, and not immediately recognizable to the player as a specific object. Gameplay and story merge pretty seamlessly here, and some quality-of-life features, such the inclusion of gentle hints and nudges in the story itself, contribute to the smoothness.
From a technical standpoint, the exploration of the city is very smooth, using a rotating first-person view. But more importantly, it's immersive and atmospheric, with well-chosen color palettes. A few of the images are muddy enough to be hard to interpret, but most appropriately bleak and run-down.
I don't want to spoil any details beyond this, though! It's not a long game, and I recommend playing it.