The two sprites were made in about 20 minutes each. I just made these for fun, but I thought they could count towards my app. The pictures of scenery were taken in Spectrum falls, my home in Minecraft. All of the things I created for this app are in worldofrecruits if you would like to check them out for yourselves.
http://s1083.photobucket.com/albums/j395/ZeroSpectrum/?albumview=slideshowSpectrum Falls is an adventure map where your goal is to reach the abstract house. If indestructible, and if you couldn't swim UP the water like a fish, it would be a fun obstacle course. That was the idea I had.
The Atom probably took the longest to make... It wasn't necessarily the rings that made it challenging, but creating the ball in the center. First, I created a solid, floating 20x20x20 block in mid air (which took forever), then I started carving the actual sphere itself.