I'm a huge geek for Adventure Time. And like any true, dedicated geek, I want to see one of my favourite shows plastered everywhere. Even my iPhone background is of Jake. Feel free to steal it, because it is awesome.
Reddit user ungivenglory is also a big fan of Adventure Time, and he also wants to see the animated show put into other forms. That's why he made this intro sequence for a potential game -- it's not a real game, sadly -- and will hopefully prove inspiration for someone to pick up on the idea.
I'm not necessarily sold on the 8-bit scheme, or the idea of a puzzle/beat-em-up game that the creator suggests. His thoughts were, "Imagine A Boy and his Blob meets Double Dragon, Puzzle/Beat-em-up." Another Reddit user suggested he look into Kickstarter, which is proving to be useful for both established and budding developers. We may yet see more of this new invention (*crosses fingers*).