Sheng Xiao and che Rong agreed to Zhao Hai's suggestion. The hidden fog beasts liked to live underground. They could live better underground. So, it was the best choice to have some hidden fog beasts to deal with the rats.
As for the explosive mustard seed beast, Zhao Hai was not ready to promote it in the sea exploration sect yet. The key was that it was too dangerous and its reproductive ability was too amazing. Only a small number of people in the sea exploration sect used it. In Zhao Hai's opinion, it was something that needed to be strictly controlled.
Explosive mustard beasts were actually very small microorganisms with great explosive power. Not many people in the sea exploration sect could use them now, and Zhao Hai did not dare to let them use them casually, so they had not been promoted much.