曹爽
In 239, Cao Rui died and was succeeded by his adopted son, Cao Fang, who became the new Wei emperor. As Cao Fang was still young then, Cao Shuang ruled on his behalf as a regent. Cao Shuang appointed Li Sheng as the Prefect of Luoyang. In 244, he was reassigned to be a Chief Clerk () under his friend Xiahou Xuan, who then held the position of General Who Attacks the West (). In the same year, Li Sheng and Deng Yang advised Cao Shuang to launch a military campaign against Wei's rival state, Shu, to boost his fame and authority in Wei. Cao Shuang's co-regent, Sima Yi, strongly objected but Cao Shuang ignored him and went ahead. The Wei forces were subsequently defeated at the Battle of Xingshi against Shu forces and suffered heavy casualties.