How does the personality of any of the major character change in the course of The Iliad?

In "The Iliad," Achilles undergoes a significant transformation in his personality. Initially consumed by pride and rage over Agamemnon's insult, he withdraws from battle, allowing his anger to dictate his actions. However, following the death of his close friend Patroclus, Achilles experiences profound grief and remorse, leading him to rejoin the fight. This shift reflects his evolution from a self-centered warrior to a more complex character who grApples with the concepts of honor, loss, and mortality.