Celtic CubeAlso named "cubic face turning deltoidal icositetrahedron"
Celtic FraudIt seems to be another Celtic Cube but it is a doubled version of the 4 Corners Cube.
CheesexahedronA 3-layer-cheese in shape of a platonic solid. In this case it is a hexahedron.
Circus SkewbA Fisher Skewb with pieces swapped to look like a twister cube.
Clematis CubeA hybrid puzzle which combines edge turns with corner turns that allow 60° turns.
Clover bandageA clover Cube with one half of the possible turns bandaged in a single block.
Clover Cube PlusPlusA modification of the Clover Cube in which the inventor split up the wing pieces.
Collider CubeA face turning tetrakis hexahedron in the shape of a cube.
Confusion CubeA triangular prism with three layers in shape of a cube but with an awkwarly reoriented axis system.