Landquaker: The Great Iron War, Book 4

As the Resistance recuperates from the recapture of Blackout, they set their sights on a daunting new objective: the massive steam-powered railway gun known as the Landquaker, a key component of the Iron Wall. To tackle this challenge, Jacob and his allies reach out to both old friends and new, enlisting support from land-loving tribes and roving biker gangs. With the Landquaker engineered to face a multitude of threats, the stakes are high as they prepare for a battle that promises to shake the very ground beneath them.