Trifecta

Our entry in the Naef Toy Competition consists of twelve triangular pyramids - only half are shown above - which come in three distinct sizes. The four smaller pyramids can stack into the four mid-sized pyramids which can then stack into the four largest pyramids.

All twelve pyramids can be arranged into one large four-sided pyramid...

... or into a cube.

They can also be stacked or arranged in numerous other ways. This toy provides plenty of leeway for them the user to be creative.