Hydra

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

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

Abilities
Hydra have a high regeneration abilities making them able to heal from any serious wound. 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 in the Great Lake.