[6] Due to her favour with the Emperor, her uncle Li was made Cavalry Commandant and her kinsman Zhi placed in charge of cadets.
[7] In September 237, Consort Guo's increasing favor led to a fatal incident with Cao Rui's former favourite, Empress Mao.
Cao Rui killed a number of his attendants whom he suspected of leaking the news, and ordered Empress Mao to commit suicide.
Cao Shuang has traditionally been considered a corrupt and incompetent regent, his centralizing reforms and his choice of controversial officials like the philosophers He Yan and Wang Bi alienating members of the court with their libertine excesses.
Though the Zhengshi period under Cao Shuang is known as a time of intellectual brilliance and his regime as reformist, the attitudes of He Yan and others clashed with the interests and views of Sima Yi's supporters.
In 254, possibly with the connivance of the Emperor, Cao Fang's inlaws the Zhen family, Li Feng and others plotted to replace Sima Shi with the famed kinsman Xiahou Xuan.
The first plot failed as Li Feng's son was denied permission to come to court (thus unable to bring his troops from Yu province).
Then on 27th March, Sima Shi discovered a second plot, this time to assassinate him during a ceremony to promote a concubine of Cao Fang.
[28] However, Pei Songzhi questions the tale as one of the people involved was already dead over the Li Feng plot while Carl Leban and Albert Dien view the account with scepticism.
Cao Fang's reign would not finish the year, either because of his role in the plots or simply because he was no longer credible as a willing Emperor to abdicate the throne to the Simas,[31] On the 17th of October, he was deposed at the age of 23.
Broken by the threat and realizing she couldn't stop the plan, the Empress Dowager summoned the seals of office needed for the abdication and Guo Zhi returned to a delighted Sima Shi.
Cao Mao, although only 13 years old, was known for his intelligence and Empress Dowager Guo might have believed that he might have had a chance of counteracting the Simas while his youth brought time.
[32][34][37] In 255, declaring that they had received a secret edict from Empress Dowager Guo,[16] experienced generals Guanqiu Jian and Wen Qin made a failed attempt to overthrow Sima Shi, by starting a rebellion from Shouchun (壽春; present-day Shou County, Anhui).
Under Fu Gu and Zhong Hui's advice, however, Sima Zhao returned to Luoyang anyway against edict, and was able to maintain control of the government.
Indeed, from that point on, he would not let Cao Mao or Empress Dowager Guo to be out of his control, and when Zhuge Dan made a failed rebellion in 257, believing that Sima Zhao would soon usurp the throne, Sima Zhao would insist on the emperor and the empress dowager accompanying him on the campaign against Zhuge Dan.
In 260, Cao Mao, not being able to make much headway in his attempt to reduce Sima Zhao's hold on power, tried to start a coup d'état himself with the imperial guards loyal to him, and after initial successes near the palace, was nevertheless killed in battle.