Number of casts: 18. Difficulty: Medium. I decided to try to build an entire pyramid using the Skematic Pyramid mold. This proved to be more difficult than I first thought, because the mold only has a few angled pieces. That meant that by the time I was done, I had lots of regular blocks lefto ver for another project. The top of the pyramid comes off, revealing a secret room. I also decided to try a different color scheme, more reminiscent of Egyptian or Aztec pyramids.