Equestria Daily's Artist Training Ground the 2nd! Draw a pony wearing armor or in uniform~
One thing I like about the new personality and design of Luna in the second season is that it's much easier to see her turning into Nightmare Moon. So for this picture, I wanted an armored Luna that really walked that line.
In my head, this is Luna on the verge of becoming Nightmare Moon, before she's banished to the moon. I wonder how bad Celestia would have let things get before finally giving up and resorting to such a desperate measure.