Rise of the Runelords

The Lost Coast – A Solo Pathfinder Campaign

This solo campaign began as an experiment—an attempt to have an AI-driven Dungeon Master run the classic Rise of the Runelords Adventure Path using Pathfinder 1e rules. Early sessions focused on fidelity to the published material, with the AI following Paizo's text and mechanics as closely as possible.

But after many hours of gameplay and experimentation, one truth became clear: the current state of AI isn't quite capable of perfectly replicating a published Adventure Path with strict rule adherence. And that's okay.

What emerged instead was something unique—something personal. A rich, improvisational story rooted in the setting of Varisia, told through the eyes of a single player character. A narrative that draws from the source material, but is no longer bound by it.

The result is The Lost Coast: a solo RPG campaign using Pathfinder 1e as a loose framework, but no longer beholden to any particular structure. It's an open-ended journey filled with discovery, emotion, and mythic undercurrents.

A Story of Mystery, Magic, and Rising Power

This is the tale of Cassian Valerius, the seventh son of a minor Taldan noble house. Scholar. Conjurer. Wanderer. Disinherited by birth order but driven by purpose, he came to Varisia seeking independence, arcane mastery, and perhaps, a legacy of his own.

What he found instead was a town on the edge of darkness.

What Makes This Story Special?

This isn’t just a game. It’s a slowly unfolding tale of mystery and destiny, told in the style of a classic fantasy novel—with a single protagonist, and choices that truly matter.

Cassian Valerius isn’t a chosen one. He’s not prophesied to save the world. But the world is changing—and he’s standing at the threshold.

Whether you’re a Pathfinder fan, a worldbuilder, or just someone who loves a good fantasy story told one chapter at a time, this is your invitation to step into the world of Golarion, seen through one man’s eyes.

Themes and Tone

This campaign leans into:

  • High fantasy wonder mixed with moments of eerie suspense

  • Ancient empires, lost knowledge, and the cost of power

  • Character-driven storytelling, emotional nuance, and evolving relationships

  • A vivid cast of NPCs who feel alive, flawed, and worth caring about

  • A journey from quiet beginnings to epic stakes

About the AI

This campaign is run by AI using GPT-4, trained to act as a Dungeon Master for a solo player. The AI improvises scenes, manages NPCs, presents challenges, and helps build a persistent world that reacts to the player’s choices. Dice rolls, spellcasting, and Pathfinder mechanics are all woven into the storytelling—but always in service of the narrative.

If you’re looking for a strict, rules-as-written AI Dungeon Master running a published Adventure Path exactly as written, the technology isn’t quite there yet. But if you’re looking for an immersive solo campaign where story and character take the lead, this experiment proves it can be done.

Welcome to The Lost Coast.

The Runelords Were Only the Beginning.

Their magic lingers in runes, in ruins, in whispers.

And Cassian has begun to listen.