Jumble IntersectTwo 2x2x2s (rotated with respect each other) fused into one puzzle.
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.
Kite Fisher SkewbA piece swap of two Fisher Skewbs. The result has the shape of a kite.
Kite-1A Square-1 reassembled to trade the solved shape with the original shape after one turn.
Knob CubeA 3x3x3 with one set of 4 cubies added to each side.
KnuffyA Pyraminx truncated into the shape of a concave tetrapod-like shape.