Cao Shuang
In 249, while Cao Shuang and the emperor Cao Fang were away at the Gaoping Tombs, Sima Yi used the opportunity to stage a "coup d'état" against Cao Shuang and seized control of Luoyang. Cao Shuang surrendered to Sima Yi after the latter promised him that he and his family would be unharmed if he gave up his powers as regent. Later, Sima Yi broke his promise as he had Cao Shuang and his supporters (including Deng Yang) arrested, charged with treason, and executed along with their families.