Thermal Shroomtoise

In Pikmin: Ultimate Doom
The Thermal Shroomtoise is a boss located in Deathbone Desert on Duron. It's fiery nature suggests that it may have evolved a natural preference to shells with magma inside. Research shows that there is a symbiotic relationship between the mushroom Fungiius and the Tortoii. The Tortoii carries the Fungiius on its back, inside the well-protected magma shell. That being said, the boss has two "phases", with two health bars. Both species can attack the Pikmin and captains with fire and poison attacks, respectively.