The Shake King is the main antagonist of the Wii video game Wario Land: Shake It!. In the game, he is the leader of a gang of pirates. He's taken control of the Shake Dimension and has come in possession of the bottomless bag which features an unlimited amount of coins and even kidnapped Princess Merelda. A citizen who was also kidnapped managed to escape and asked Wario, the protagonist of the game, for help. He agreed and entered the Shake Dimension.
In Japan, his name is Shay King, which when put together sounds like "shaking".