Hwanung (환웅): A son of the god in the heavenly world. He had longed to live in the surface world for long until
he was finally given permission to do so. He was said to have brought three Guardians of the world: the Blue Dragon, the White
Tiger and the Black Turtle-snake. After marrying a woman who was born as a bear, he had a son and returned to the Heaven.
His heavenly artifact is the Cheongung (천궁) which normally takes the form of a fancy cylinder and enlarges
to form a glowing white bow. It is said to be able to either kill or give life to anyone it shoots. It is used to kill the
leader of the Hwacheon clan in the last episode. And its destruction means the death of the King of Jushin and the unsummoning
of the Heavenly power.
- Blue Dragon (청룡/Cheong-Ryong): The ruler of the East and the guardian of the clouds, hence the alternative name Unsa
(운사/雲師: Cloudmaster).
Its heavenly artifact is a bluish stone that looks slightly like a shellfish. It is said to activate when "The King of
Jushin feels 'cold mercy' in his heart." When activated, it can weaken the power of the wielder of fire. It was also shown
to speed the healing of its master when in physical contact with him.
- White Tiger (백호/Baek-Ho): The ruler of the West and the guardian of the winds, hence the alternative name Pungbaek
(풍백/風伯: Windleader).
Its heavenly artifact is a white twisted piece of metal. It awakens when "The King of Jushin feels 'pure courage' in his
heart."
- Black Turtle-Snake (현무/Hyeon-Mu): The ruler of the North and the guardian of the rain, hence the alternative name Usa
(우사/雨師: Rainmaster).
Its heavenly artifact is a black cylinder that is usually shaped as a long twisted walking stick. It awakens when "The
King of Jushin feels 'dark rage' in his heart." When it awakens, the time stops along with everything other than its master
and the King of Jushin, enabling the leader of the Four Guardians to identify the King.
- Crimson Sparrow (주작/Jujak): The ruler of the South and the guardian of the fire. It is not a subordinate of Hwanung, and
was portrayed as becoming evil when its 'host' is engulfed with anger. Unlike its actual incarnation, it controls fire, resembling
Bonghwang (봉황) more than Jujak.
Its heavenly artifact is a large red gem orb. It awakens when "The King of Jushin feels 'burning passion' in his heart."
It glows in red when activated.
For the first time in Korea, a king has been associated with the Four Gods. King Gwanggaeto is generally considered as one of the greatest rulers in the history of Korea. The Four Guardians were found engraved in
his tomb (as in any other king's), inspiring the drama.
