He Liao, Diao

Diao becomes an expert in blowing poisonous needles from the hollow bamboo stem which she acquires from the 2nd assassin who is defeated by Xin sent to kill all 3 of them.

Bi later finds out that Diao is a girl after she gets injured in the chest and he removes her grass armor to stop the bleeding.

After getting trained under Chang Pin, Diao later becomes the tactician of the Fei Xin Force.