Jumble IntersectTwo 2x2x2s (rotated with respect each other) fused into one puzzle.
Jumble PebbleA jumbling only puzzle with a strange yet unnamed geometry. It resembles the jumble rock.
Jumble RockA jumbling puzzle built around an unusual, currently unnamed shape.
JumblixA puzzle with the axis system of a face-turning pentagonal dipyramid. Ten of 12 possible moves only jumbling.
Junior Cross CubesA fully functional lower-order cross cube made with four Rubik's 2x2x2s.
K-CubeA self-made 2x2x3 with extensions.
Key+Lock CubeA puzzle consisting of two cubes and with two solutions. Two 3x3x3's with some pieces glued on one face.
KnuffyA Pyraminx truncated into the shape of a concave tetrapod-like shape.
Leaf CubeA truncated 3x3x3 puzzle in the shape of leaves.
Lethal WeaponThis is just a shape transformation to a 3x3x3 cube. It is similar to the theme of the Extended Cube.
Magic Morphix setA 2x3x3 and 1x3x3 transformed in a way that they result in a curved tetrahedron.