Petbottom

A PET Bottom is one of the many enemies that appear in the Game Boy Advance game, Wario Land 4. They only appear in the Ruby Passage, and resemble a bottle full of a pink liquid, which has a sharp spear attached to the front of the cap. They have legs and they walk back and forth. The only threatening part of a PET Bottom is the spear. Wario can defeat a PET Bottom by either ground pounding the top side of the enemy, ramming the non-sharp side, or by doing a S-ground pound nearby; the PET Bottom will flip upside down and Wario can attack the underside.

The "PET" part of the name stands for "Polyethylene terephthalate", is a thermoplastic polymer resin of the polyester family and is used in synthetic fibers, such as bottles.