Empress Bulblax

The Empress Bulblax is a boss-class enemy in the Pikmin games. It resembles the head of a Dwarf Red Bulborb stuck onto a monstrous, elongated backside that accounts as its egg sac. It can't eat the Pikmin due to its size, which makes its head hang a good few feet above the ground. The only way to defeat it is to throw Pikmin at its face. After a while, it will shake the Pikmin off and roll left and right in an attempt to crush them, usually making rocks fall in the process. It is one of the few bosses that can vary depending on where you encounter it, since later dungeons have the Empress continuously giving birth to Bulborb Larvae out of its backside. They can get killed by the Empress' rolling, so they aren't a problem when the actual face-to-face fight starts.

They are loctated on the last sublevel (5) of the Hole of Beasts, Sublevel 8 of the Frontier Cavern, Sublevel 11 of the Hole of Heroes, and Sublevel 4 of the Emperor's Realm in Challenge Mode.