i was taken off guard by how much i liked the atmosphere on this one. the climb up the mountain is abundant with intense vignettes that build up tension as you go. i love the description of phasing - it's grotesque. and, i think, interestingly placed in a game about climbing. the image of alternate versions of these townsfolk tumbling down the mountain and then snapping back to flat ground is compelling.
for the routes, are the modifiers (soft plants, rushing water) like, details that players can use to their advantage, or flavor text for you to bring in after they make a route assessment? i checked out the mountain resonance rules (which are very cool), but still wasn't able to get a good feel on using these
high: the constant attention paid to the fact that fireworks are always bursting overhead, starting from the very first segment. what a striking image! very cool detail to anchor my narration when GMing.
low: the melody source table - i don't mind that the ways to resist it are random, but i'm cold on the actual source not being defined. it's a major detail, but the lack of definition makes it feel disconnected from the rest of the town, especially notable since the text otherwise feels tightly woven. i think in my ideal version of this, you pin down one source for the melody and hint at it throughout some other segments/events to elevate the whole package.
great work on the cover design too!