What qualities enabled Buck to triumph over Spitz?

Buck triumphed over Spitz due to his adaptability, intelligence, and growing instincts as a sled dog. His ability to learn quickly from his experiences and understand the dynamics of the pack gave him an advantage. Additionally, Buck's determination and fierce spirit allowed him to confront Spitz effectively, ultimately leading to his victory in their fierce rivalry. These qualities not only helped him defeat Spitz but also solidified his position as the leader of the pack.