Cheng Han
In 347, after the ambitious general Huan Wen, without the imperial government's approval, carried out a campaign against and destroyed Cheng Han, annexing Cheng Han territory to Jin, the imperial government became apprehensive that Huan would use this opportunity to take over. Sima Yu thus invited the official Yin Hao, who was considered able, to join him and Cai in making important decisions, to counter Huan's influence. In 350, after Cai had repeatedly declined greater honor conferred him by the emperor, Yin accused Cai of disrespecting imperial authority and had him removed, seizing more power than he had before.