I remember when linked me the originalAdventure Time animated short [link] a few years ago and it totally made my week. I also thought to myself, "It'd be absolutely brilliant if this was an actual TV show."
Fast forward a bit and it is!
Anyway, a really great series. Ice King, LSP and Tree trunks are my favorites. ;d
Edit: Oh yea here's the rough lines on my Tumblr [link]
Edit: Yes, this was on Cartoon Network's promo: [link]