Ma Su
Cao Cao defends against Shu's attacks, with Xiahou Yuan defeating Huang Zhong at Mt. Dingjun in 218 AD after a failed prisoner exchange. Zhuge Liang then makes a new attempt to go north, appointing Ma Su as a subordinate, but Ma Su is encircled at Jieting in 229 AD and his army is decimated by Sima Yi, Cao Cao's strategist. Cao Cao and Sima Yi then defeat Zhuge Liang at the Wuzhang Plains in 234 AD, defeating (or killing, depending on order of conquest) Liu Bei. If Wu has fallen first, Cao Cao proceeds to attack the Shu capital of Chengdu. He gets Wei Yan to defect to his forces and the Wei army seizes both Luo Castle and Chengdu from the Shu forces, and Liu Bei and his peasant militias are killed.