Hydra

Hydras (ヒドラ) are massive serpent-like monster with multiple heads that live in the Great Lake.

Appearance
Hydra have multiple serpentine, snake like heads, and sharp curved teeth. Its has webbed feet, a serpent tail and a thick strong body.

Abilities
Hydras have high regeneration abilities, making them able to heal from any serious wounds. At their birth, a baby hydra would normally possess eight heads. As they grow into adulthood the number would increase to twelve.

Known Hydra

 * Rororo

Trivia

 * While not explicitly stated, hydras seem to be indigenous to the Great Lake.