As the name suggests, it's merely a replacement for the moon from the removed Day/Night Cycle, and looks to be inflated like a balloon.


You find the Cipher Key here, and nothing else as of 0.9.9.

To access False Moon, get caught in the rain on Violet Meteorite, enter the waterfall cave and befriend the Gryphon. Later you can find him on a cliff and he will fly you there.