Light Yagami's actions in the anime "Death Note" significantly affect his sense of morality throughout the series. At the beginning, he believes he is justified in using the Death Note to eliminate criminals and create a utopian society. However, as he becomes more consumed by power and the consequences of his actions unfold, his morality becomes increasingly distorted. He starts justifying more extreme measures and rationalizing his unethical behavior, ultimately leading to a complete transformation of his moral compass.