This is the original scene I modeled before placing him on Cloud Nine. I painstakingly researched the original Space Invaders designs for his T-shirt, too!

Turnaround:

I used a combination of modeling and sculpting techniques. On this head detail, for instance:

• The base meshes for head and shirt were subdivided a few times, then sculpted – to keep the topology intact.
• A multiresolution modifier on the ears helped to define their shape.
• The ear tufts are profile curves.