Chen Tai
In the autumn of 249, Jiang Wei led Shu forces on a fourth invasion of Wei and built two fortresses at Qushan (麴山; southeast of present-day Min County, Gansu), which were respectively guarded by the Shu officers Ju An () and Li Xin (). He also contacted the Qiang tribes and requested assistance from them in harassing the Wei-controlled commanderies in Yong Province. After discussing with Chen Tai, the Inspector of Yong Province, Guo Huai ordered him, Xu Zhi and Deng Ai to lead Wei forces to attack the Shu fortresses at Qushan and cut off their food and water supplies. Ju An and Li Xin led their men to taunt Deng Ai to attack them, but Deng Ai ignored them. As time passed, the two fortresses gradually ran out of supplies. Jiang Wei led his troops from Mount Niutou (牛頭山; west of present-day Zhaohua District, Guangyuan, Sichuan) to reinforce the fortresses. They encountered Chen Tai and his army along the way. Chen Tai ordered his army to build forts to resist Jiang Wei and his troops but refrain from engaging the enemy. At the same time, he also wrote to Guo Huai and requested his help in attacking Mount Niutou. Guo Huai did so and led his forces across the Tao River in preparation for attacking Mount Niutou.