非常之谋

Explanation: Is: not common. Not an ordinary plot. Refers to the plot to usurp the throne. 　　Source: "Han Xiao Cheng Zhao Queen Biography" pass away there must be very variable, and is a very plot. " 　　Examples: Wei Yi also deterred a large barrow, ~, difficult to burst. (Ming Zhang Pu, "five tombstones in mind")