After obtaining the Death Note, Light Yagami's personality undergoes a significant transformation. He becomes more arrogant, manipulative, and power-hungry. His sense of justice becomes warped as he starts to see himself as a god-like figure who can decide who lives and who dies. Light becomes increasingly detached from his original moral values and becomes consumed by his desire to create a world free of criminals, even if it means resorting to extreme and unethical methods. His transformation into the vigilante known as "Kira" leads him down a dark path, causing him to lose touch with his humanity and become a ruthless and calculating individual.
