The irony of King Alfonso VI
The King is the supreme leader in his territory, and he makes final decisions on all matters that concern his leadership. Ironically, the King is angry at El Cid because he argues that he forced him to swear that he is not responsible for his brother's death. The reader asks the question, who has the power to force the King to make any form of confession? Therefore, the King's claims are entirely sardonic.
El Cid’s marriage to Dona
El Cid believes that if he marries the King's cousin, Dona, he will restore his relationship with the King. Ironically, the marriage makes their relationship worse because El Cid is forced to run into exile. The King grows even angrier with El Cid, and he does not extend any favor to him.
The Princes’ satire
El Cid restores his owner and his honor, and his daughters are given express authority to marry the King's nephews. Ironically, the King's nephews (princes) are not interested in El Cid's daughters but want to steal part of his fortune. Therefore, El Cid's expected sons-in-law have bad intentions towards him and his fortune.
Omniscient Narrator
Presenting more information than the characters have, this deliberate omniscient narrator creates a gap between the expectations of the public and that of the protagonists who lead the play towards a tone of dramatic irony. As an example, we can refer to the moment in which the infants of Carrión take the daughters of the Cid: the audience knows that they plan to mistreat them but the hero, even knowing that something is "wrong", lets them go without his protection. Another case of irony, for example, is the episode of the loan of the coffers to the Jews Rachel and Vidas: the public knows, together with the Cid, that they are mostly full of sand but those greedy people assume is full of riches.
