Fantasma Libro Hydra

Audible

Hydra                                            

Orenda Books

Hydra: 2 (Six Stories)                          

Yearling

Hydra                                            

Torch Graphic Press

The Hydra's Venomous Blood (The Secret Society of Monster Hunters)

Scholastic

Hydrant-Hydra: Volume 4 (The Binder of Doom, 4)  

Deadman's Tome Jr The Hydra (English Edition)    

Pushkin Children's Books

The Trouble with the Two-Headed Hydra (Miss Mary-Kate Martin's Guide to Monsters)

Aladdin Paperbacks

Hercules and the Nine-Headed Hydra: 16 (Heroes in Training, 16)

Hydra Publications

Talitha: A Haunting                              

iUniverse

The Adventures of Jewel Cardwell: Hydra’S Nest (English Edition)