The Arya chapters serve another purpose beyond exploring the power of misinformation and uncertainty: it shows her growing into a vengeful killer. Since her first appearance in Game of Thrones, Arya has aspired to be a warrior, and she has shown a fair amount of skill and determination on that front. Although she has fought in self-defense several times in the books, up to this point she has not seemed capable of killing in cold blood. But with the depiction of her repeating the names of the people she wants to kill to herself every night before bed, the novel shows Arya starting to harden as she prepares herself to enact vengeance on those who have wronged her or her family. The arrival of Jaqen at Harrenhal furthers this development. For the first time, Arya can exercise the power of life and death over others, even if just by proxy. Arya consequently takes her first steps toward revenge, and the novel shows her unrepentant about being responsible for another person's death.
Bran’s chapter furthers his development as well and points to an interesting and enigmatic future for his character. Although Bran denies Jojen’s claim about his special abilities and his connection with Summer, readers have already seen this connection growing stronger. In a notable scene, as Bran grows angry, so does Summer, so much so that Bran cannot call Summer back to him. It is clear from this episode that Bran has an undeniable psychic connection with his wolf, but it is one he is as yet unable to fully control. Luwin’s sensible explanation may appear to satisfy Bran for the time being, but the foreshadowing regarding Bran’s abilities and destiny strongly suggests that the issue is not settled and Bran's supernatural link with his direwolf will play a great role in his future and in the novel.