So the planet works a lot like our moon. One side is always facing the sun, the other is always turned away.

Normally, this would make a planet uninhabitable, but there's also a large moon. The moon cuts across the sun side of the planet, allowing for just enough shade a 'day' to create a strip of land that is habitable.

As the moon travels across the sky, the darkness follows, but it's only very dark in the spot where the moon is, like an eclipse.

The way the water works is where the sun and darkness meet, the ice melts, creating rivers that flow over the Life belt. Outside of the Life belt, the water evaporates in the desert. Most of the rain falls on the dark side, renewing the ice fields.

Unfortunately, this is also why the planet is dying. The sun is old in this system, and reaching the end of its life. It's getting hotter. The desert is encroaching the Life belt and choking off the rivers.

Does that make sense?

Thank you,

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"I try to create sympathy for my characters, then turn the monsters loose."
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