Final answer:
The repeated use of the word "destroyed" emphasizes the character's passion and ferocity and suggests a vengeful intention, which is a literary device known as anaphora.
Step-by-step explanation:
The repetition of the word "destroyed" in the phrase "I'll kill him and destroy his whole family in return for my father and brothers destroyed" does indicate ferocity and passion. This literary device, which is known as anaphora, enhances the emotional intensity of the statement and conveys the character's deep-seated anger and desire for revenge. When an author chooses to repeat a word or phrase, it is often done to emphasize a particular emotion or theme within the text. In this case, the repetition underscores the speaker’s vehement and passionate response to a familial loss, elevating the sense of a relentless pursuit of vengeance.