I came up with her for the March design challenge at
This is the version with the full background. The pony alone is here: [link]
They pick a color scheme and you design a pony for it. It's a weird bunch of colors but it kind of grew on me (like a fungus, get it?) after a while. The combination of very light pinky-tan and dark blue and gray made me think of a pale mushroom growing in a dark, dank, cold forest. That sounds kind of creepy and depressing, so I decided to make the pony herself very cheerful-looking in expression. She is to mushrooms what Applejack is to apples, and clearly she loves her job.
Edited the basic vector I made for Sew-and-So, with some modifications to the body, whole new mane, tail, cutie mark and eyes, and added teeth.