The four Dragon Kings are, in Chinese mythology

Chinese mythology

Chinese mythology is a collection of cultural history, folktales, and religions that have been passed down in oral or written tradition. These include creation myths and legends and myths concerning the founding of Chinese culture and the Chinese state...

, the divine rulers of the four sea

Sea

A sea generally refers to a large body of salt water, but the term is used in other contexts as well. Most commonly, it means a large expanse of saline water connected with an ocean, and is commonly used as a synonym for ocean...

s (each sea corresponding to one of the cardinal directions). Although Dragon Kings appear in their true forms as dragons

Chinese dragon

Chinese dragons are legendary creatures in Chinese mythology and folklore, with mythic counterparts among Japanese, Korean, Vietnamese, Bhutanese, Western and Turkic dragons. In Chinese art, dragons are typically portrayed as long, scaled, serpentine creatures with four legs...

, they have the ability to shapeshift into human

Human

Humans are the only living species in the Homo genus...

 form. The Dragon Kings live in crystal

Crystal

A crystal or crystalline solid is a solid material whose constituent atoms, molecules, or ions are arranged in an orderly repeating pattern extending in all three spatial dimensions. The scientific study of crystals and crystal formation is known as crystallography...

 palace

Palace

A palace is a grand residence, especially a royal residence or the home of a head of state or some other high-ranking dignitary, such as a bishop or archbishop. The word itself is derived from the Latin name Palātium, for Palatine Hill, one of the seven hills in Rome. In many parts of Europe, the...

s, guarded by shrimp

Shrimp

Shrimp are swimming, decapod crustaceans classified in the infraorder Caridea, found widely around the world in both fresh and salt water. Adult shrimp are filter feeding benthic animals living close to the bottom. They can live in schools and can swim rapidly backwards. Shrimp are an important...

 soldiers and crab

Crab

True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...

 generals.

The Dragon Kings are:

• Dragon of the East: Ao Guang (敖廣)
• Dragon of the South: Ao Qin (敖欽)
• Dragon of the West: Ao Run (敖閏)
• Dragon of the North: Ao Shun (敖順)

Besides ruling over the aquatic life, the Dragon Kings also manipulate cloud

Cloud

A cloud is a visible mass of liquid droplets or frozen crystals made of water and/or various chemicals suspended in the atmosphere above the surface of a planetary body. They are also known as aerosols. Clouds in Earth's atmosphere are studied in the cloud physics branch of meteorology...

s and rain

Rain

Rain is liquid precipitation, as opposed to non-liquid kinds of precipitation such as snow, hail and sleet. Rain requires the presence of a thick layer of the atmosphere to have temperatures above the melting point of water near and above the Earth's surface...

.