Light Yagami's actions have a significant impact on the broader narrative themes of Death Note, particularly on the themes of power, justice, morality, and the consequences of one's actions. His use of the Death Note to eliminate criminals in the name of justice raises complex questions about the nature of good and evil, the limits of power, and the ethical implications of taking justice into one's own hands. As his character evolves throughout the series, his actions serve to challenge and explore these themes in depth, ultimately leading to a thought-provoking and morally ambiguous narrative.