Trono de cristal (Trono de Cristal 1)

After a year of hard labor in the salt mines, the young assassin Celaena Sardothien has been summoned by the prince of the Kingdom of Endovier. Celaena has not come with the intention of ending the prince's life, but with the desire to win her freedom. If she defeats twenty-three assassins, thieves, and warriors in a life-or-death competition, she will be freed from prison to serve as the royal champion.

The prince will advise her. The captain of the guard will protect her. But something evil lurks in the crystal palace, and it's there to kill. As her rivals die one by one, Celaena's fight for freedom becomes a fight for survival and a relentless search for the source of the evil before it destroys the world.