In article number 2107998, Glaucio H. Paulino and co-workers create a class of metamaterials derived from a reconfigurable origami pattern with triclinic symmetry, leading to reversible auxeticity. When the tristable unit cells are tessellated, phenomena that resemble linear and point defects emerge as a result of geometric frustration, which can be reprogrammed at desired locations. The resulting tessellations and metamaterials display tunable anisotropy and have potential applications to wave propagation control and in microrobots.