Zhong Hui's first course of action was to falsify letters proving a purported plan by Deng Ai to rebel, creating distrust between Sima Zhao and Deng Ai; this was supplemented by Deng Ai's own growing arrogance in his correspondence with Sima.
Zhong Hui immediately became acting commander of Wei forces in the former Shu territory, at which point his hubris reached its height.