I have an idea for a planet:
A separate planet cut off from the others
Name: Zion
Basic information: Farthest away from the sun, cold and freezing. Corruption takes main residence with. The humans there all serve corruption. Corruption fastens through them and all they want is change. The 2 main life forms are humans and dragons. There are other beings, but a lot of it is corrupted.
Primary biome: Corrupted wasteland. A freezing biome with a cold dead atmosphere that only corruption's blessed may survive in.
Other biomes: Lemon wastelands. Lemons are so sour that if you eat them, you get transformed into a black hole (Unless you are invested with corrupted investiture). The black holes that are generated are wrapped in corrupted investiture and only suck you in if you touch them. They float around, adding to the yellow lemony vibe. The lemons grow on lemon trees. There are myths of a paradise where the corruption is benevolent. The myths speak of them on the poles.
Common flora and fauna: Idk.
Magic system idea: A system similar to the Knights Radiant with oaths, but they are more a matter of position. Like, 'I am a shifter of the 6th oath' or something. They would be shapeshifters and would gain powers as they gain oaths. (No there are no 'spren' that regulate the oaths. Corruption it's self has to regulate it.) Corruption has the highest oath possible, and no others can reach that oath level. (Elaborated more on doc)
Edit: To avoid double posting, I'm just editing this. I made a google doc. @bmcclure7 comment I'm the owner, and I'll give you editing access. Link (Also now supports additions of suggestions, new and future! I will try and add everything I miss here, tell me if you notice anything different.!)