Thousands of fathoms deep within the ocean, a serpent begins to snake her way from the ocean floor. Her length is not measured in meters, but instead miles. As she rises to the surface, she opens her long, tube-like maw just below the ocean surface, opening up a whirlpool hundreds of meters long in diameter. As her abdomen is filled by the water, her long, serpent tail flicks and flails beneath the ocean currents, causing massive tsunamis and tidal waves. Finally, when another water is gathered, it’s sprayed out in a powerful jet high into the sky, forming a hurricane.
Hydra was not created within the holy realm, rather she ascended from the material plane into it. She has never been a sapient creature- rather she is a true beast, roaming without purpose. However, through raw strength, she gained utter dominance over the sea and storms. For this, Terra gave the last of her elemental powers to Hydra, and in the process making her a goddess, no different than the gods who took on Terra’s other elemental powers.
As Hydra is not a god of any intelligence, there are few that worship her for favors or power, instead fearing her wrath more than seeking her blessing. Those who do pray to Hydra are largely shipfarers, fishermen, or someone with a strong connection to the sea. A prayer to Hydra is done through either casting a token or offering into deep waters, such as the ocean, a river, or a lake, or blowing through a conch shell horn. Giving an offering is meant to attract her- hence give you more powers. Blowing a conch shell is meant to scare her off, and keep you safe. Her symbol is a fountain jet of water.