I was trying out different color palettes to see which one I preferred. The top palettes are based off the mimic octopus and the blue-ringed octopus, respectively. The rest aren't inspired by anything, I just thought the colors looked nice.
After completing “Moody Pumpkins” the foreground looked interesting so I removed the pumpkins modified the remaining foreground and added the trees and sky. Tree colors were selected from the foreground and other palettes.