Adumbria

Adumbria Prime is a tidally locked civilised world on the Damocles fringe: desert day-face, arctic night-face, everyone living in the twilight Shadow Belt around Skitterfall. Cain stopped the Ravagers and a Slaanesh summoning from turning it into a daemon world. Snapshot parent is The Ghost Stars; lore is Ultima / Damocles. Keep the parent.