He Yan

He Yan (onyomi: Ka An) is He Jin's grandson and one of Cao Cao's adopted sons, and was childhood friend of both Sima Shi and Xiahou Xuan. He showed incredible talent at a young age, but was disliked by others for his flamboyance and egotism; this along with repeated shaming of his talents lead to him being corrupt under Cao Shuang's rule.

Dynasty Warriors
He Yan first appears in Dynasty Warriors 7 as one of Cao Shuang's associates. He is present during Wei's brief campaign at Mt. Xingshi and is the final obstacle to the Sima family's coup against his lord.

In Dynasty Warriors 8, the defeat of He Yan and his comrades will cause Jia Chong to suspect Xiahou Ba, triggering one of the stages needed to open the hypothetical route.

Historical Information
Born in the city of Nanyang at Henan, He Yan was adopted at the age of six by Cao Cao when his mother became the latter's concubine. He never got along with Cao Pi who called him a "false son" for acting as though their father favored him. His contemporaries slandered him as effeminate, vain, and prone to dissolution. He was also said to have been addicted to hallucinogens. However, Cao Cao appreciated his intellect and was impressed by the youth's interpretations of the Art of War, often turning to him whenever he failed to understand a portion of it. He later married the Princess of Jinxiang whose wise conduct clashed with his contrary nature.

Hated by Cao Pi and his son Cao Rui, He Yan never attained any high positions during their respective reigns. He was finally promoted as minister when Cao Shuang became regent. During that time, he skillfully wrote annotations and commentaries on various works related to history and philosophy. He also analyzed the contributions of Laozi and Zhuangzi while authoring a summarized version of the Analects called the Lunyu Jijie; his book would be recognized as the most authoritative source of information for almost one thousand years. Outside of his scholastic interests, he was also a proficient poet.

Like many of Cao Shuang's associates, he was executed for treason when Sima Yi took power in 249. At the time of his death, he had a five year old son who was also slated for execution. His widow was able to hide their child before convincing the Sima clan to spare him. According to the Chronicles of the Clans of Wei, He Yan served as judge for Cao Shuang's trial. He was very severe and harsh in his judgement to earn approval, but Sima Yi still saw it fit to have him killed.

Despite his abuse of power with his position under Cao Shuang, records have shown that even one such as He Yan agreed along with Sima Shi and Dowager Guo's listed opinion that Cao Fang's lack of deeds in the state affairs would cause him to be deposed from the throne, despite the fact that several other detractors of the Sima family have argued that the Dowager was coerced into deposing him. It was also stated that He Yan did not get along with Li Feng, an adviser Sima Shi would come to trust but in reality was plotting against him.