Is “The rebellious bone at the back of his head was seen through by Zhuge Liang” true?
novel invention
According to the 'Records of the Three Kingdoms, Book of Shu, Biography of Wei Yan', Wei Yan was deeply trusted and heavily relied upon by Liu Bei; the 'rebellious bone' is entirely a fictional prediction in the 'Romance of the Three Kingdoms'.
Wei Yan
In official history, he was a key minister of Shu Han who guarded Hanzhong and achieved many military exploits, but in the novel, he is portrayed as a traitor with a 'rebellious bone' at the back of his head.