The Hydra is a B.O.W. created based on the hamerhead worm.
The Hydra is quite similar to the hammerhead worm in appearance, only much larger, spanning at about 12 meters in length.
To attack, Hydra uses its bulk to pin its prey against the ground, and then extends its tube-like mouth from its mid-ventral area, using it to pierce the flesh of its prey. Digestive enzymes are released from the mouth, dissolving the prey inside out. Finally, Hydra will suck up the liquefied remains of its prey.
What makes Hydra even more deadly than it already is, is its regenerative abilities. When severed, the separated pieces of the worm will become Hydras themselves within seconds.