The player has to fight a wild Terlard at the end of Comet Cave. Its two heads were fighting with each other, causing it to rampage and driving the other wild Pokémon crazy.
TERLARD's two heads have completely independent brains. That they ever manage to coordinate at all is a miracle.
Terlard is a two-headed, serpentine Pokémon that is always partially submerged in the ground. Each head has two rounded horns and a gray-green spot on the middle of its forehead. It has striated marks along its stomach and spots on its back. Its tail splits into two ends, each tipped with a jagged spade. Its scales are orange with gray-green spots.
Terlard are adept tunnelers, able to dig miles in a single day and disappear underground in a flash. In addition, they have access to a wide spread of physical and special techniques, owing to their dragon typing and diverse offenses. However, this is mitigated somewhat by their heads' inability to coordinate with each other. Because of this, Terlard takes careful training in order to ensure it can stay focused in battle.
Terlard are much more aggressive than their previous evolutions, due in part to their two heads' constant disagreements over food and even territory.
Terlard are nocturnal apex predators, claiming large territories within cave systems and defending them from any and all intruders. They are known to take down prey larger than themselves, such as Gararewl, by collapsing the ground underneath them, leaving them trapped and helpless.