It was small. It was subtle. It was, in fact, kind of sneaky. But hey, when you’re building a series of novels that may very well end up being over thirty books, dealing with the cosmic ramification of shattering what is essentially God across about ten planets or more, well, sometimes subtlety is okay.

But it doesn’t excuse the fact that something is up with Trell.

Warning: Spoilers for Shadows of Self, but no spoilers for the forthcoming The Bands of Mourning.

“Who?” you may ask. “Huh?” you may go. But make no mistake. Trell is a name that sparks a reaction in readers of Brandon Sanderson’s Cosmere novels—first introduced in Mistborn: The Final Empire, Trelagism is one of the dualist religions Sazed mentions to Vin during her training. And over the past two Mistborn books in the Wax and Wayne adventures, the name Trell has been getting more and more attention.

In The Alloy of Law, we get a brief mention of Trell by Miles “Hundredlives” Dagouter, the gold twinborn thief who was using his gold compounding to essentially become immortal, and who believed that those who were Metalborn were somehow divine. Miles claimed to worship Trell and believed that Trell created mankind, but whether or not he was a Trelagist is not clear; he referred to his religion as “Trellism,” and all signs point to worship of Trell, whatever it is.

And in Shadows of Self, when they’re examining the spike that gave Paalm her allomantic and feruchemical abilities—something that no spike should be able to give to a kandra—Marasi learned that even Harmony cannot identify the metal used for the spike, which terrified the ever-living heck out of her. She then thinks back to her interactions with Miles, and vows to determine who or what Trell is.

You and me both, Marasi.

So what do we know about Trell? Not much. Not really. But the fact is, Trelagism/Trellism is more than just a religion. Whoever its adherents are, Trell itself is a force acting upon the world of Scadrial, and Harmony doesn’t know a single damn thing about it. Trell seems to be seeding Scadrial with its influence, and actively manipulating events through the use of its own magic. Trell appears to be a force of great change, one that is very eager to get things moving on Scadrial. So we don’t know a lot, but the being called Trell has been mentioned too often to just be a passing hint.

So who could it be?

Odium: The Big Bad. The Master of Evil. The Great Hate. Whatever ’90s-wrestler-name you want to use, this is a huge possibility. While relegated to the Rosharan star system, trapped there by the actions of the Heralds, Odium still knows what’s going on in the larger Cosmere, and has no love for Harmony. Why he would decide to influence Scadrial, or even how, has no answers at the moment. But his basic mission of destruction, dominance, and chaos line up with Miles’s intense belief in ruling as a Twinborn, and Paalm’s mission to overthrow the city of Elendel. Whether or not it’s really Odium remains to be seen, but there’s good evidence.

Another Shard: It may not be Odium at all, but that doesn’t mean it’s not a Shard. With the destruction of Leras and Ati, the original holders of Preservation and Ruin, who’s to say there isn’t some larger Shardic force in the Cosmere going, “Hey, what the hell?” Each Shard is a mystery—even the ones we’ve met across the Cosmere—and so it’s not outside the realm of possibility that another Shard, either by conscious choice or by fulfilling their own Shardic Intent, is coming after Harmony and Scadrial.

Something New Entirely: The Cosmere is huge, and Sanderson has wheels within wheels within wheels we don’t even know about yet. I would be totally unsurprised to learn that Trell is some new threat from some far off veil. But I doubt it. Still, who knows?

Total Wildcard Theory: Trell is just a local punk rock band using their music to mess with allomancers. They post really obnoxious fliers all around Elendel: “Please support Trell’s newest CD, listen to them on the radio tonight at 9.” “Sign up for our mailing list, new CDs and interviews at your door, only a steelpush away. Tshirts are twenty boxings, koloss sizes are extra.” “New track, “Tineye Blind,” now up for your listening pleasure at Spotify.”

…

Just saying… it’s a possibility.

In any case, I’ll be very curious to see who Trell may be, and what secrets Brandon has yet to reveal!

Read the first six chapters of the next Mistborn novel, The Bands of Mourning, starting with Chapter One.

Martin Cahill tried eating metal once but it just made him sick. When he’s not slinging words at Tor.com, he’s contributing to Book Riot and Strange Horizons. You can find him on Twitter @McflyCahill90. Tweet him about delicious east coast IPAs, ideas on who Rey’s parents are, and your worries about the DC Movie Universe.