Probably, yeah. Definitely can't be good for them. I'm not a biologist, but I encourage anyone reading this to chime in! What happens to cave-dwelling creatures when brought out into the sun for an extended period?

I didn't make it clear in my original comment, but in my head I imagined a race whose explorers swore off venturing into the darkness after the first few disappearances. Maybe some folklore emerged, and they assumed that "that place" and death are intrinsically related. Then, as their tech became more advanced, they gained the ability to scrutinize the other planets in their star system. Imagine the horror when they see "death" wandering along the surface (rather, the surface moving through it) and they have no clue why theirs isn't moving.

Is it merely asleep?

This was a fun thought experiment. Thanks for getting my brain churning! I'd love to read someone's expansion on this idea, if anyone else finds it fascinating. At this point in the lore, I can see religions being born to try and appease Death, or at least prolong its slumber in the frozen hemisphere while they search for answers. Wars are fought, nations fall, yada yada... Maybe it's best not to draw too many parallels with our own world 😁