8. Arya Stark
On the one hand – the one holding the sword, most likely – watching a sweet little tomboy turn into the Punisher of Westeros before our very eyes is as much fun as Game of Thrones gets, especially given actor Maisie Williams' precocious talent. On the other hand, she's a child gradually losing all respect for human life – a slow-motion tragedy, and one of the series' most complex character arcs. Now a fully trained assassin, she's returned to the battleground to avenge her still-beloved family, making her Westeros's number-one wild card.