Little background on this one:
There used to be a show on Adult Swim called Metalocalypse. The show was co-created by a dude named Brendon Small. He wrote the music and did most of the voices of the main characters. He was a very busy man. The show has since been canceled due to a falling out between the owner of either Adult Swim or the company that owns Adult Swim. When Brendon Small started a crowdfunding campaign to purchase the show to make a final season independently, it was a success. Unfortunately the network refused to sell Metalocalypse, purely because they are dicks and hate Brendon Small. He has since gone on to make one of my favorite albums of all time, Galaktikon 2.
With that little bit of background out of the way, here's a documentary that came with the special edition of "Dethalbum 3."