Cao Mao (241-260) was son of Cao Lin and grandson of Cao Pi, and the 4th Emperor of Wei. Though young, he was extremely talented. He frequently debated with his ministers and out-reasoned them. During Zhuge Dan's rebellion, he went to watch the battle. Angered at Sima Zhao's tyranny, he raised a few troops, but one of his advisers reported on him and he failed. He was killed by Cheng Ji at Jia Chong's command.