According to the Records of the Three Kingdoms, Dian Wei once defended Cao Cao and Lu Bu in the battle of Puyang, holding more than ten halberds and yelling at Lu Bu and his men.
He was named the Tiger Hou by Cao Cao and became Cao Cao's bodyguard. He discovered the conspiracy of Xu and others to murder Cao Cao, won the trust of Cao Cao, and kept him around.