The Terminators sent by those rulers had all been beaten to a pulp by Ji Fengyan and now laid useless in bed. This was undoubtedly a slight by Ji Fengyan towards their kingdoms. They were unwilling to swallow this indignity.
As such, the various rulers had gathered to discuss, and sought the Mo Shi Emperor to help them teach Ji Fengyan a lesson.
The status of the Kingdom of Sa Er was beyond reach. If the ruler of a normal nation came to them with a request, they would not even be granted an audience with the Sa Er Emperor. Many of the rulers had been in the capital city for several days, and none of them had met the Sa Er Emperor even once.
On the other hand, the Kingdom of Mo Shi had interacted with most of the nations because of their fondness of war, and was also easily incited into a fight. That was why those rulers had come over to stir things up.