Yu Suzuki : Lan Di (Rantei-Souryu/藍帝(蒼龍)) is the east leader. His name also means Blue Dragon. About Niao Sun, she also has another name : 炎帝 (Entei), and rules over the South part and is represented by a Phoenix.
Now, regarding the last 2 bosses, no one has seen them yet. One of them is Koutei (昊帝) and leads the West part and is represented by a Tiger. The last one is Gentei (玄帝), covers the North part and is represented by a Turtle.
Oh and, Ziming Hong is not one of the 4th leaders.
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