Hydra, are rare, powerful Yokai, who are well known for their regeneration abilities, and their multiple heads.
Hydra are most commonly found in swamp like biomes, since they prefer moist, warm environments. They rarely go to interact with other Yokai, and instead stay in seclusion.
Hydra are average sized, draconic beasts with a serpentine visage. Most of them are roughly six feet at the shoulder, and twenty feet long. They have multicolored scales, with yellow eyes. They have very sharp teeth, with protrusions similar to beaks on their upper jaw. Their mouths are capable of opening very wide. The amount of heads a Hydra has can vary between individuals, and is often a way of measuring their age, or experience
Most Hydra are greedy and arrogant, with a habit of looking down on all other Yokai, since they have the ability to regenerate from any injury they are given. Some Hydra, will even look down on each other, and view ones with fewer heads as inferior. There is normally a single dominant head, which is normally the Hydra's original head, and controls the entire function of the monster. The others have individual minds, but they have no control over the body.
Fitting to their appearance, Hydras are strictly meat eaters. They will split their kill between heads, with the dominant head generally getting the lions share.
All Hydra are capable of regenerating from any injury their sustain. When one of their heads are cut off, two more will replace it. One of the heads is the head that was cut off, and the other is a newly developed one. Each one of the heads is capable of communicating telepathically with one another. This allows them work to work in near perfect synch.
Hydra's saliva holds naturally acidic properties, and if necessary, they will exhale strongly, which releases the saliva in the form of a noxious, highly acidic gas. The gas itself, is green, and takes time to fully dissipate. Hydra also have a potent venom in their fangs, capable of killing anything in a short space of time.
One of their only weaknesses of a Hydra, is that they are unable to regenerate from cauterized wounds, or injuries inflicted by fire.