It’s like Chekhov might have said, had he been a Game of Thrones fan: You don’t introduce a windswept castle with towers held together with swinging rope bridges if you’re not eventually going to toss someone off one of those bridges. And on Sunday night’s episode, we finally got our answer, when Balon Greyjoy met his end via bridge fall. (Not a hard guess, since GOT’s Pyke scenes usually feature a cast of … two.) But who was the hooded man who tossed the would-be king of the Iron Islands to his death? That’s Balon’s younger brother Euron and if you had trouble keeping up with the dialogue in that scene, here’s what you need to know about him.

In George R.R. Martin’s novels, Euron is the second-eldest of five Greyjoy brothers, though it seems the show has consolidated them somewhat. He makes his first appearance at the beginning of A Feast for Crows, sailing into the Iron Islands the day after Balon’s death. (That’s probably not a coincidence; Martin drops clues that Euron hired a Faceless Man to do the job for him.) He’d been exiled years before, for the crime of sleeping with one of his brothers’ wives, which, because the Ironborn are terrible, led to the brother beating his wife to death. His reappearance understandably freaks people out a little bit, because Euron isn’t quite like the rest of the Ironborn. He captains a ship called Silence — so called because he’s had the crew’s tongues ripped out — and claims to have raided all around the world, from the ruins of Valyria to the mysterious shadow-city of Asshai. There’s a bit of the schoolyard braggart to Euron: He also claims he once possessed a dragon egg, but conveniently threw it overboard in fit of pique. (That one sounds like a stretch, but it could explain how he paid the Faceless Man.)

There’s one uniting element to all these tales: Euron is from the Iron Islands, but not of them. While the rest of his countrymen cling bitterly to the Old Way and their religion, Euron takes a more expansive view of evil. He had an encounter with the Three-Eyed Raven as a youth, which would indicate he has skin-changing ability akin to Bran’s. He visited Qarth shortly after Daenerys left, appropriating the magical powers of that city’s blue-lipped Warlocks, and was later linked by prophecy to the White Walkers. He openly mocks his brothers’ faith in the Drowned God; in his villainy and his narcissism, Euron is his own god. Or, as he put it to Balon Sunday night, “From Oldtown to Qarth, when men see my sails, they pray.” He expands on this thought in Feast: “I spill their blood upon the sea and sow their screaming women with my seed. Their little gods cannot stop me, so plainly they are false gods.”

And while Euron has his eye set on ruling the Ironborn, like a certain presidential candidate he’s not going to let that stop him from reveling in naked contempt for his own constituents. “I had forgotten what a small and noisy folk they are, my Ironborn,” he tells his brother midway through Feast for Crows. But just like that candidate, it would be a mistake to think of Euron purely as a figure of camp. There are hints throughout the books that he sexually abused at least one of his brothers as a child, an incident that seems to foreshadow his eventual worldview. The Ironborn rape and pillage Westeros because they are indifferent to others’ pain; for Euron, pain is the point. As the Tumblr blogger Poor Quentyn puts it:

[Euron] is not culturally Ironborn at all. He is a fully integrated citizen of the global misery-economy; he is the epitome of the horrorshow-helix that we see throughout Dany’s chapters … He belongs to the flux, the slipstream, the spaces he can exploit to achieve his personal catharsis in causing pain, in a manner untethered to the Old Way … Euron conquers and absorbs ideologies, reaching into the story source code to bring meta-narratives to their knees and force them to work for him.

In short, Euron isn’t a pirate, he’s “a monster wearing a pirate suit.”

So where does he go from here? First, he’s got to get through the kingsmoot, the Ironborn practice of electing their new kings. From there, it will be fascinating to see how much of Euron’s book story line makes it to the show. The rest of his brothers have seemingly been cut for time — though the Ironborn priest seen in episode two may turn out to be his youngest brother, Aeron — and the show’s untangling of George R.R. Martin’s Meereenese Knot may mean that TV-Euron will take a different short-term path towards achieving his goals. But in the long term? Well, there’s a reason Song of Ice and Fire fandom has been debating a scenario they call the “Eldritch apocalypse.” You don’t introduce a new villain this late in the game if he’s not going to make a major splash, and Euron’s presence is a sign that, finally, Game of Thrones’ political and magical plot threads may be starting to merge.