Records of the Three Kingdoms
Cheng Yu, courtesy name Zhongde, was from Dong’e in Dong commandery. His original name was Cheng Li. He dreamed that he held the sun in both hands, and Cao Cao renamed him Yu, “the sun elevated.” In 194, while Cao Cao was campaigning in Xu Province, Zhang Miao and Chen Gong brought Lü Bu in as governor of Yan. Most of the cities rebelled. Cheng Yu and Xun Yu held Juancheng, Fan, and Dong’e. Cao Cao had a place to return to.
He later became a general, was enfeoffed, and joined discussions of Yuan Shao, Liu Bei, and Sun Quan. He was harsh and made enemies. In 220, after Cao Pi took the imperial title, he retired and died the same year, at eighty.
Romance of the Three Kingdoms
In the novel Cheng Yu is an old counselor in Cao Cao’s tent, often reading an enemy beside Xun Yu and Guo Jia. The defense of the three cities is sometimes written into the early Yan Province fighting.
He has fewer scenes than Guo Jia and is not made into a man who calculates the whole later war. Around Cao Pi’s accession he leaves the foreground.
Reference: Wikipedia · Cheng Yu