Link to this animation should be found in the dictionary/encyclopedia next to the definition of "Mad Skilz"

Hard-koa

Audio is from this video: http://www.youtube.com/watch?v=InZNBcJTmWs Animation is also based on that video.

That page says the source audio (except for the Sesame Street clips at the start and end) is "A Divine Proclamation for Finishing the Present Existence" performed by the band Last Days of Humanity.

There's a version of this video on Youtube as well, but this one has better picture quality.

Hmm... I notice that Patchouli and Koakuma are doing their crazy expressions from the sound test.

How did I manage to watch this all...

*clicks and unselects play*
OH GOD!

LOL what the hell was that?! Epic drum solo = melted brain