Tetracore was shown to me at IPP by my friend Haym Hirsh. His friend Jared McComb had designed it and he let me play with it at dinner one evening. The fact that this puzzle has 5 symmetry solutions does not mean it is easy! There are many other nonsymetric solutions that are equally difficult. I still have not solved it. The premise is that you have a core piece that gets surrounded by 7 pairs of tetracubes, creating a 4x4x4 cube. 64 cubes + 768 beveled edges + 76 holes + 76 magnets = A challenge to make and solve!