Wei Yan 魏延

Fact vs. Fiction
Historically...
 * ...Wei Yan did not murder Han Xuan and then surrendered to Liu Bei with Huang Zhong. Han Xuan surrendered to Liu Bei.
 * ...Wei Yan was not a general under Han Xuan or Liu Biao, but just a common soldier who rose to the rank of general under Liu Bei.
 * ...Wei Yan did not slay the fictional character Cao Zun.
 * ...Wei Yan did not kill Wang Shuang.