Duelling was a type of formal combat between two or more witches or wizards – where only magical acts could be used as a form of offence or attack. Before a duel, the opponents would bow to show their mutual respect and then wait for a count of three to start. Although some duels ended in death, students were also able to practice the art of duelling at Hogwarts and it also existed as a competitive sport with rigorous rules about the curses, hexes and charms allowed to be used.