Guardians

The Guardians (Japanese: ガーデイアン, Gādeian, Korean: 가디언, Gadieon, Hebrew: השומרים) are protectors of Quarton. They are known as Zephyrus, Boreas, Eurus, and Notus.

About
Long ago, the Guardians would assemble the Quartonians to honor the Tenkai Knights, the greatest wielders of Tenkai Energy. When Vilius's lust for Tenkai Energy reached the tipping point and consumed him, the Guardians made the decision to dismiss him from the Tenkai Knights.

Vilius returned later with a Corrupted army to attack them with his newly discovered ability to absorb the Tenkai Energy. Vilius himself managed to ambush the Guardians and attempted to drain them of all their energy. The Knights pushed back the Corrupted army's attack and arrived at the Guardians' Chambers to rescue them. The Knights reached the Guardians' Chambers in time to face Vilius and rescue Boreas.

During the war that came after, the Guardians watched as Vilius awakened the Tenkai Dragon.

Years later, Guardian Boreas went to Earth in search of the new Tenkai Knights. Lately, the Guardians have argued whether or not to be involved in the war between Vilius and the Corekai.

In the Series
In "A New Knight", they all agreed to stop Vilius from controlling the two worlds. They used a shield to protect the Knights from being hit by the blast of the Evil Tenkai Dragon and used an ancient spell to seal the dragon, so the Knights could revive the Tenkai Dragon by using the White Key.

In "Vilius Returns", they revived Vilius, which caused him to take the Guardians energy to make him more superior than them. They were held prisoners by him, and the evil Guardians were a darker gray with a red full eye. However, the "red full eye" scene is only seen in Vilius' new "sky fortress."

In "Dojo Mojo", Boreas confronts the Knights in his evil form. As the Knights are confused of why Boreas is agianst them, Boreas summons Guardian Megafusion for the first time to destroy the Knights, but fails.

Trivia

 * For the first seventeen episodes, Boreas is the only guardian known by name.
 * "The Key to Evil" reveals the name of Guardian Eurus.
 * "Dragon Key Quest" reveals the green Guardian's name as Zephyrus.
 * "Vilius Returns" reveals the yellow Guardian's name as Notus.
 * Boreas is the only Guardian to have the same name in English and Japanese. For the other Guardians, their names are switched only in the Japanese version, meaning that Eurus is named Notus, Notus is named Zephyrus, and Zephyrus is named Eurus.
 * The Guardian's names, colors, and home is based off of the four chief Greek wind gods from ancient Greek mythology: Boreas (North Winter wind), Notus (South Summer wind), Eurus (East Autumn wind), and Zephyrus (West Spring wind).
 * It may be possible that the Guardians created everything including the planet Quarton.
 * All of the Guardians names, except for Boreas, end with "us".