Light Yagami's actions in the anime "Death Note" have a significant impact on his own morality. Initially, Light believes that he is acting for the greater good by using the Death Note to eliminate criminals and create a utopia free of crime. However, as he continues to use the Death Note and become more power-hungry, his morality becomes increasingly skewed. He becomes willing to sacrifice innocent lives and manipulate others to achieve his goals, leading to a gradual decline in his moral values. Ultimately, Light's actions lead him to question his own sense of right and wrong, blurring the lines between justice and tyranny.