Crazy RTA Crazy 4x4x4 in shape of a Rhombic Triacontahedron.
Crazy Senior BarrelThe crazy variant of the Senior Barrel with one fixed circles and one floating.
Crazy Square-1A Square-1 with two circles, one on the top face and the other on the bottom face. These two faces have different movements.
Crazy Super LooperThree circles on one line, each allowing 180° turns with deeper intersections. Plus four additional inner circles.
Crescent CubeA hybrid of corner and edge turning cube a little bit more complex than the simplest possible.
CrosskubeTwo fishered 2x2x2s fused into one compound solid.
Crucifix CubeA 2x2x2 related to the Cross Cube but only to two dimensions.
Cube 3x3x3 LockedA 3x3x3 with 24 plungers. A concept with great potential that is not realized yet.
Cubic 3x5x7 IIA cubic 3x5x7 3D-printed from scratch as if it was bandaged 8x8x8.