A while ago I got approached by a Publisher in America that's working on the Official Art of Adventure Time book. They want to have a section that includes art done by other people based on existing characters from the show. The following renders are what they selected to include. I had to re-render them out over the Christmas Holidays and due to them being done in 4K resolution (for printing), it took 3 days to render out each. This meant I had very little computer time during the 9 days because every resource was being used. The first attempt had already crashed once during the first day, so after I had restarted the render, I just left it to run it's course.
These are based on the characters Beemo and Peppermint Butler:
Programs used were 3ds Max 2011 (for compatibility with an older version of Vray Render) and Photoshop CS6 for post-processing.