Charon
Heavy witch and druid presence, Charon is said to have untapped mystical properties, and followers of the occult have been trying to unlock its secrets for decades. Toppling over one another in a endless battle to tap this "well" of it's spectra, perfect for mages to study or barbarians and warlords to find a new power supply.
Often avoided out of expectations of piracy or murder, the world tree Charon grew was immediately corrupted and turned the spillways of water into rivers of blood. Said to be highly cursed, no reported visitors have returned, and few are bold enough to try.
The most consistent landmark of this moon is its network of blood ice volcanoes, we have yet to figure out where this blood is coming from but it leaves a bloody stain at the northern peak of the moon where they're most concentrated, there is very minimal plant or animal life here as it is an extremely testing atmosphere to thrive in.
In spite of this, it has become the seat of the throne of the disgraced King, Severian. After failing to lead his army to victory against the Lizars King Therias. Losing his kingdom of Hydra, he has been banished alone to this horrible place. He is looking to rebuild and take his throne back from Therias.