My son designed this minecraft creeper as a birthday present for a friend of his. It has a detachable head and hollow body for stashing stuff inside (and this also means the head can swivel on the body)

You will need reasonably well tuned bridging to print this. Use a low infill density so the non-hollow bits don't use too much plastic (I used 0.1). Also, make sure you have exterior support enabled to look after the face and exterior of the neck. There will be a little dangling on the inside-top of the neck, (on a test print I didn't worry about it and just cleaned it up afterward, on the real print I just gave some manual support with a screwdriver when printing).

At the current sizing you'll need a mendel-sized build platform. The total assembled creeper height is 200mm (pretty big, and it uses a fair bit of plastic). There are parameters in the scad if you want to make it smaller or otherwise adjust things.