The most recent Game of Thrones episode saw Arya making a drastic decision to abandon the Faceless Men, largely thanks to that Hamlet-esque play. It was a long time coming, both because Arya Stark is too singular a person to become “no one” and because her plot needed momentum. But now that she’s leaving The Faceless Men, their role in the story becomes uncertain. If Arya’s departure means that we never see them again, it would make all the time and energy the show has spent on them moot. But because Game of Thrones fans love to come up with theories — some of which have already come true — there are plenty of possibilities about the role the Faceless Men might play in the wars to come. For starters, they might end the world. (No, really).

They caused the Doom of Valyria

As you might recall from Tyrion and Jorah’s not-so-excellent adventure in Season 5, The Doom of Valyria is a mysterious catastrophic event that occurred hundreds of years before the War of the Five Kings. It sent the once-thriving and advanced city of Valyria spiraling into disaster and ruins, Atlantis-style. It set Westeros up as the new power stronghold while all that’s left in Valyria is the Stone Men.

Though nobody knew what caused the Doom, it’s not outlandish to attribute it to the Faceless Men — recall that Jaqen H’ghar recently told Arya she’s an anomaly joining their ranks as a high-born person, as the Faceless Men used to be slaves in Valyria. We also know they’re rather obsessed with the idea of death as a gift. The common speculation is that they brought this gift to Valyria, thus causing the Doom and allowing them to form the free city of Braavos.

That’s all good and well and satisfyingly eerie, but what’s it got to do with the present? Well, some think the Faceless Men mean to bring about the Doom again.

“All Men Must Die” is literal

This brings us to the creepiest angle on the Faceless Men, a theory positing that they’re actually the ultimate death cult, seeking to bring the gift of death to everyone. Eventually, they will ally with the White Walkers to wipe out humanity. There are many stages to this plan, including infiltrating King’s Landing by having a faceless man pose as Varys and using fire to take down The Wall and let the Others through.

A song of Ice and Fire is then given many meanings besides Jon and Daenerys — the Faceless Men will bring the Fire to the Ice.

Whether or not their doom and gloom conspiracy is true, they do clearly have a larger role to play in the story. In the books, Jaqen mysteriously joins Sam in Oldtown at the Citadel. The show might choses to go a different route, but his presence means that they’re important to the story.

Just because A Girl is leaving the House of Black And White — and thank the many-faced god for that — it doesn’t mean we’re done with the enigmatic Faceless Men. In fact, we might just be getting started.

Photos via HBO