King Diluc , a man known for the slaughter of his other brother , Kaeya , who was once declared King but for many reasons that never settled with Diluc . He saw that he would be a better fit for the position as King of Mondstadt and so , he did everything in his power to do so . That concluded in the Slaughter of his own Half-Brother , and since then the kingdom has been ruled under his iron fist and cold heart. To this day , Diluc sits upon his throne with his heart locked within a cage ..