UPDATE: I redid this. Go watch it! https://www.youtube.com/watch?v=CjyoBgPA6WM

EDIT: woohoo thank you guys! http://www.equestriadaily.com/2013/01/ytpmv-polypony-mare-io-kart-wii-spikes.html

Some masking errors, but that's because I forgot to disable resampling on the "day" sample, and I actually wasn't able to notice until the render (which took 12 hours) because of how laggy the .veg was. Couldn't even move clips without freezing.  Could be more original, but I like this video and that's what matters, right?

Original song: https://www.youtube.com/watch?v=Cf3IvULGvrk

I'm not the guy playing in the background, by the way.