I'm currently doing an MA in Games Art and Design in the University of Hertfordshire. At the start of the year we did a bunch of week long projects. The aim was not to produce game-ready assets, but just to explore ideas and techniques. Now we have eight weeks to fully develop two of those ideas (two four-week projects).
This was my output of one of those short projects. I'm going to make some modifications to this and hopefully by the end, present it in UE4.
Here is the slightly adjusted concept. I'm going to have a more modern balloon (no netting) and I'll tone down the colours. I'll abandon the idea of the top of the envelope mophing into the top of his head. The cut line of the head has been moved up and I did away with the brains inside the skull - too body horror. Instead I'm trying to go for a slightly psychedelic vibe, but I don't want it to look cartoonishly colourful either.