I begun to imagine shapes invading other styles, replacing their elements while keeping the structure. Decellularization: you remove the tissue until only the scaffold remains. This process involves huge freedom, in the sense that you have a rich, but structured workspace. It has some obvious and nonobvious constraints: one has to respect, eventually, materials found in the real world and its very lawful physics. Also, you never know if you explored the search-space at all its branches.