Coup d'etat: A sudden overthrow of a government by a small group within the state establishment often involving violence. Like if all your chess pieces suddenly turned against you!
Regicide: The act of killing a king. In our chess analogy this would be checkmate – game over!
Political Martyrdom: When someone dies for their beliefs and becomes an inspiration for others after their death. It's like if your taken chess piece becomes a symbol that motivates the rest of your pieces to fight harder.