Arya and Hound are making their way towards the castle. The portcullis opens, soldiers come out, the fighting begins. Actually it's not much of a fight, Robb's troops are massacred and burnt alive in their party tents.
Never should have trusted those Freys! But I get the feeling massacring your wedding guests is so unthinkable that nobody thought it...
The Hound wants to get Arya away from there but she wants to go to her mother. She is so close! Arya runs and is chased by the Hound and is hit on the head with an axe.
She is not dead. I refuse to believe it. Even GRRM would not give a character so much development only to kill her now. Would he?