Marowak

Even with Marowak's huge Attack stat when bolstered by Thick Club and near-unresisted coverage, Marowak is too slow and defensively vulnerable to function well as a wallbreaker. Marowak's dependence on its item makes it quite weak once it is removed, and when combined with its many weaknesses, it makes Marowak demand too much support to be a viable choice. Other Ground-types like Rhydon and Piloswine, while weaker, have far more bulk along with secondary typings that allow them to function more consistently as offensive tanks, and wallbreakers like Choice Band Sawk and Thwackey can perform better thanks to their far higher Speed.