As many of you have pointed out with the Vinyl Scratch plug a while back, Scribblenauts Unlimited had a bit of pony. It looks like it went beyond that though, with the inclusion of Changelings and Twilight Sparkle's crown/gala dress to go along with it. I wonder what else is hidden in the game from FiM? The word combos make it hard to dig around!
Thanks to XSAlien for the screenshot!