Throne of Glass (2012)

After serving a year in the brutal salt mines of Endovier, Celaena is offered a chance at freedom by Prince Dorian Havilliard. She must compete in a tournament to become the king's champion, a position that comes with the promise of eventual freedom. As she navigates the dangerous competition, which includes various deadly tasks against other skilled assassins, she forms complex relationships with Dorian and his loyal friend, Captain Chaol Westfall. However, as competitors start dying under mysterious circumstances, Celaena uncovers a deeper threat that involves dark magic and a malevolent force that is linked to the royal family. The novel blends elements of fantasy, action, and romance, establishing a captivating world where Celaena must confront her own demons while deciding who she can trust.