It seems like Arya has been working to become one of the Faceless Men who serve the Many-Faced God on Game of Thrones for about four thousand years now. She only recently got her sight back, and was given one final chance to prove that she could be one of them. Well, as some of us suspected, Arya isn't exactly cut out for life as a girl with no name. She failed to complete her task of murdering the lead actress of the Braavos theater troupe, and instead went to dig Needle out of it's hiding place to finally become Arya Stark again. Now that she has shunned the Many-Faced God, will Arya die on Game of Thrones Season 6? It seems the Waif may kill her.
Yes, if the Waif has anything to say about it, Arya will definitely die. Jaqen H'ghar just gave her permission to snuff out Arya as punishment for her insolence. Of course, Jaqen made sure to instruct her to limit Arya's suffering, but she seems to take some pleasure in causing Arya pain. It definitely doesn't look great for Arya, but I can't imagine she could be taken out so easily. It seems like her journey with the Faceless Men can't end like this without some sort of payoff.
Maybe the theories about the Waif are true. Maybe she's actually Arya's former fighting instructor, Syrio Forel. There are some seriously compelling pieces of evidence to back it up, and it would be a huge twist that could save Arya from whatever consequences possibly await her for her failure to act for the God of Death. Let's just hope she remembers how to use Needle.