Brad Wardell describes Sorcerer King simply: “You’re Gondor, and Sauron has the Ring. He got Frodo.”
It’s an interesting place to start a fantasy 4X: you’ve already lost the familiar contest for supremacy. Another faction triggered the endgame and relegated everyone else to an historical footnote. That ruler has become the Sorcerer King.
Meanwhile, you’re the last holdout, trying to mount a resistance with just one city against an empire. To borrow another phrase from Wardell, it’s The Alamo as a 4X strategy game.

“We kind of wanted to flip the whole concept [of the fantasy 4X] on its head.,” Wardell says. “Where the AI player is the one really playing the 4X game, per se, but he’s playing a very different one.”
In keeping with Sorcerer King’s theme of being an “epilogue” to an unseen fantasy 4X, diplomacy is not about competition between factions. Everyone is simply reacting to the fact that the Sorcerer King is now the dominant power.