The rivalry between Light Yagami and L, as well as Near, in the anime "Death Note" is significant because it drives the central conflict of the story.
L is a brilliant detective trying to catch Kira (Light Yagami) and uncover his true identity, while Near takes on a similar role after L's demise. Their intellectual sparring and strategic maneuvering create intense suspense and twists in the plot, making the cat-and-mouse game between Light and his adversaries a crucial element of the narrative.
Additionally, the rivalry highlights the themes of justice, morality, and the consequences of wielding power, as both sides believe they are fighting for what they perceive as right. Ultimately, the complex dynamics between Light, L, and Near add depth and tension to the story, making it a compelling exploration of the battle between good and evil.