When the PCs witness their hometown of Phaendar destroyed in the first steps of an all-out war of conquest, they begin a quest that leads them from desperate survival to heroes of legend as they push back against the monstrous Ironfang Legion. This ruthless army—helmed by the hobgoblin General Azaersi and empowered by an ancient artifact known as the Onyx Key—intends to claim both Nirmathas and Molthune while the isolated nations bicker with one another. The heroes' quest will take them deep into the fey-haunted Fangwood Forest, to the craggy bluffs of western Nirmathas, and delve deep into the earth to explore the Darklands. Can a small band of refugees grow into champions and push back against Azaersi's horde, or will the Ironfang Invasion give way to an Ironfang nation?
The Ironfang Invasion Adventure Path calls back to classic adventures, focusing on exploring the unknown and confronting the fantastic, all to stop a monstrous enemy from wiping out the good people of Nirmathas and Molthune. The PCs will delve into dungeons, siege well-guarded keeps, explore the wilderness, and battle some of the most iconic creatures from the 40-year history of fantasy RPGs.
- Trail of the Hunted (1 of 6): In the war-torn nation of Nirmathas, far from the battlefront, the sleepy little town of Phaendar is rocked by the sudden appearance of an overwhelming foe! The heroes must flee their homes, saving whatever friends and supplies they can, as the monstrous Ironfang Legion and their insidious General Azaersi begin carving out an empire of monsters from the dregs of Nirmathas and Molthune alike. The heroes must guard their band of survivors in the wilderness, challenge a troglodyte tribe for safe haven, and face the brutal bounty hunters dispatched to end their flight to freedom!
- Fangs of War (2 of 6): With their colony of survivors safe for the moment, the heroes must scour the wilderness of the Fangwood for resources, and make contact with anyone who can help them strike back against the invading Ironfang Legion. But as they push into the wilds, all signs point to the legendary Chernasardo Rangers being wiped out or imprisoned by the merciless black dragon Ibzairiak! The heroes must face hostile fey and mythical beasts now claiming the ruined fortresses left in the dragon's wake in order to save what remains of these legendary freedom fighters and begin the foundation of their own army!
- Assault on Longshadow (3 of 6): Having rescued what remains of the Chernasardo Rangers, the heroes have their first chance to take the offensive against the Ironfang Legion when rumors emerge of the monstrous invaders massing to the north to siege the refinery town of Longshadow. If the Legion succeeds, their inhuman empire tightens its grip across western Nirmathas, and the mines and refineries would grant them all the raw materials their engine of war requires. But the Legion's heavy focus on Longshadow leaves their flanks vulnerable to a campaign of sabotage and harassment! Can the PCs end the hobgoblin siege, and in the process discover the secret behind the Ironfang Legion's lightning-quick raids and unseen troop movements?
- Siege of Stone (4 of 6): The Ironfang Legion's secret weapon has been revealed! An ancient dwarven artifact known as the Stone Road allows the hobgoblins to move their forces hundreds of miles at a time, completely unseen. Whatever secrets—and vulnerabilities—the Stone Road may have lie sealed within the dwarven Sky Citadel of Kraggodan. To enter the besieged fortress-city, the heroes must brave the dangers of the Darklands, including morlock fanatics and their slithering god, and duergar slavers, only to find what they need in long-abandoned corners of the ancient city now dominated by horrors from deep below
- Prisoners of the Blight (5 of 6): With the secrets of the Stone Road and its focus, the Onyx Citadel, finally revealed, the PCs only need an army of their own to push back against the Ironfang Legion. But with Nirmathas's ragtag forces occupied with Molthune and the Legion tearing at the nation’s underbelly, the heroes require unconventional allies to build that army. Legends tell of an ancient fey nation that once controlled the Fangwood Forest, and now lies imprisoned by the corrupted dryad Arlantia and her otherworldly Darkblight. Can the heroes survive this twisted, fey wonderland and defeat its mistress, or will they succumb to the same sentient plants, terrifying dragon, and legendary beasts that have claimed so many before them?
- Vault of the Onyx Citadel (6 of 6): With an army of their own, the heroes finally wage war against the Ironfang Legion in the climactic conclusion of the Ironfang Invasion Adventure Path! To end the hobgoblin threat once and for all, they must assault the Onyx Citadel—an ancient fortress on the Plane of Earth constructed eons ago by the mysterious Vault Builders—explore its alien landscape, and undermine the inhuman forces. Can the heroes fight their way past the Ironfang Legion’s greatest leaders and confront General Azaersi before she activates her ultimate weapon: A doomsday device that will wipe out not only Nirmathas, but the surrounding nations as well?