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This video shows two fascinating rhombic zonohedra. On the left, RT30 = the rhombic tetracontrahedron; on the right RE90 = the rhombic enneacontrahedron. These polyhedra possess lots of degree-three vertices which act as "corners" that can be interpreted as convex or concave, much like in a rhombic tiling of the plane. The underlying constraint graphs (in green) has all cycles pentagonal (RT30) or a mix of pentagons and hexagons (RE90). The odd constraint cycles have nontrivial monodromy and highlight both an absolute H^1 class as well as a nontrivial relative H^2 class. When the video fades to wireframe, the rotational ambiguity is strong, even though the system is drawn with over- and under-crossings faithfully.