The fourth episode of "Game of Thrones" season 7, "The Spoils of War," featured a compelling fight between Arya Stark and Brienne of Tarth. Arya's ability with the sword is amazing. She uses a combination of fighting tactics she has absorbed over the years, as you can see from the following analysis.

Arya's fighting style

It's easy to recognize Syrio Forel's training. The nimble moves, the fluid, and graceful movements Arya has come from her training in the Braavosi Water Dance discipline. Arya's final smile also reminds us of the way she used to smile out of happiness during Syrio's lessons.

Arya has also learned a lot from the Hound. Her attacks on Brienne's most vulnerable areas (neck, hands, legs, and knees) show that she remembers the time she attacked the Hound's armored chest without inflicting any damage. After having stabbed him in the armor in season 4, she received a powerful slap in the face. The Hound's lessons are hard to forget...

Arya's ability to bounce back from a hit, ducking and dodging when she's disarmed comes straight from her training with Jaqen and The Waif.

Arya's most badass move

Just before the end of the sparring session, we can see Arya unsheathing her Valyrian steel dagger. Brienne tries to end the fight by grabbing the hand that is holding the weapon, but Arya immediately changes the blade from right hand to left hand.

Brienne went for the wrist control to disarm her opponent, and Arya just switched hands in less than a second.

You can appreciate this amazing move at 1:06 in the following video:

Arya fights left-handed, but Maisie Williams is right-handed

It's interesting to note that Maisie Williams, who plays Arya Stark in the TV series, is actually right-handed.

Arya is left-handed in the show as well as in the books. A while ago, Williams talked about this in an interview with TV Guide. She explained that her mom told her about Arya being left-handed. "From then on," Williams said, "I was like, 'Alright, I'm going to try to do everything left-handed.' When I was practicing out in the garden and things I would do left-handed just to feel that rhythm." As we all saw during her fight with Brienne, Williams' training in real life paid off in the end.

Don't forget: the fifth episode of "Game of Thrones" Season 7, titled "Eastwatch," airs on August 13, on HBO. Here's the next episode's summary: "Daenerys demands loyalty from the surviving Lannister soldiers; Jon heeds Bran’s warning about White Walkers on the move; Cersei vows to vanquish anyone or anything that stands in her way."