What does the green light represent?

The three-day day patrol passed just like that. That night, Xu Qi 'an, song tingfeng, and Zhu guangxiao formed a team. They were wearing black uniforms and short capes. A Gong hung on their chest and a knife hung on their waists. They walked on the streets of the inner city with ease.

The night gradually cooled, and the flowers fell to the ground and turned into frost.

The capital was silent at night. It was winter, and there were no chirping of insects or chirping of birds. It was so quiet that Xu Qi 'an felt like he was in a leisurely countryside.

From time to time, he could hear uniform footsteps and the clattering of armor plates.

They were the Imperial saber guards who patrolled the city.

After patrolling the streets for an hour, song tingfeng and his two colleagues jumped onto the top of a small building and looked down at the crisscrossing streets.