북벌
Cao Zhen starts to play a more important role from Chapter 91 onwards when the Shu regent Zhuge Liang launches the Northern Expeditions against Wei. His contributions in the series of battles against Shu are largely downplayed because the author, Luo Guanzhong, wanted to accentuate Sima Yi's resourcefulness and effectively portray him as Zhuge Liang's nemesis. Luo Guanzhong even attributed Cao Zhen's death to his failure to heed Sima Yi's forewarning of a Shu offensive.