I had to check out Proto-Martian Archives to get a sense of the system and things clicked way better after that. Thematically, this feels like the kind of world a planetary romance hero would stumble upon, so lots of points there. The factions only existing in the trial and manifesting as people from the player(s)'s past is a neat touch given the doomed nature of the Sap Kin. Given that it's a solo/duet system, I wonder if some guidance could be given on how to run something like this as a true solo. Seems like it'd be difficult to not spoil something in the caverns.
Great illustrations and good layout. I think the reading order is a little muddled as a spread, but workable.