Cheng Wu 程武

In Chapter 92 of the Romance, when Zhuge Liang led his army to Mianyang, the Wei ruler Cao Rui sent the imperial son-in-law Xiahou Mao to gather troops from the various routes of Guanzhong and resist him. Xiahou Mao made Han De, a great general of Xiliang who had come with 80,000 Western Qiang troops, his vanguard. But at Mount Fengming Zhao Yun came out alone, killed Han De's eldest son Han Ying and third son Han Qiong, knocked his fourth son Han Qi (韓琪) from his horse with his spear and captured his second son Han Yao alive, whereupon Han De fled back into his lines first and the Xiliang troops were badly defeated. Romance, Ch. 92 §1 · 4–8 · 11

Xiahou Mao came out leading his troops in person, but even Han De, who charged in vowing to avenge his four sons, died on Zhao Yun's spear in fewer than three bouts, and the Wei army fell back more than ten li and pitched camp. When Xiahou Mao deliberated with his generals through the night, asking what was to be done since no one could stand against Zhao Yun, the Army Adviser Cheng Wu, son of Cheng Yu, came forward and said that Zhao Yun had courage but no strategy and was not worth worrying about. He said that the next day the Commander should again lead the troops out, but should first lay two bodies of troops in ambush on both sides; on meeting in battle he should fall back first and lure Zhao Yun to where the ambush lay, then climb the hill and direct the troops on all sides to surround him in layer upon layer, and Zhao Yun could then be captured. Romance, Ch. 92 §12–14

Xiahou Mao followed his advice and gave Dong Xi and Xue Ze 30,000 troops each to lie in ambush on the left and the right. The next day the Wei general Pan Sui fled without fighting even three bouts, and eight generals, letting Xiahou Mao go first, fled one after another; Zhao Yun, riding his momentum, pushed deep into enemy ground, and Deng Zhi, who had few troops, could not rescue him. From the top of the hill Xiahou Mao directed the three armies, pointing east when Zhao Yun went east and west when he went west, so that Zhao Yun fought from the hour of chen in the morning until the hour of you in the evening and still could not break out. When night fell and crossbow bolts rained down from all sides, Zhao Yun sighed that, having refused to admit his age, he would now die in this place. Romance, Ch. 92 §15–19

Just then Zhang Bao, sent by the Chancellor, killed Xue Ze, who was blocking the way, and Guan Xing, having cut down Dong Xi whom he met on the battlefield, broke in and rescued Zhao Yun. That night the troops of the three routes attacked from both sides and routed the Wei army, and Xiahou Mao fled to Nan'an Commandery with more than a hundred brave officers of his headquarters and shut the city gates tight. After this the Romance does not bring Cheng Wu onstage again. Romance, Ch. 92 §19–23