As Wulf and Rymstrydle continue their journey to Drakenroost, they encounter a caravan under attack by the hideous Rat Men.

Together, they manage to fight off the Rat Men, but they must move quickly for the Rat Men will soon return in force. They head for the safety of the Iron Citadel, a huge steel mill.

It is at the Iron Citadel that they encounter Modeo Doh Tyrak, controller of the Citadel and step son of Mordek Mal Moriak, the man responsible for the death of Wulf's parents.

Modeo, however, has no love for his step father, who exiled him to the Iron Citadel many years ago. Modeo converted the Citadel from a barely functioning factory into well oiled, productive steel mill. Modeo foolishly thinks that Mordek is unaware of all that he has accomplished at the Iron Citadel, including the Iron Colossus, a creature of metal capable of massive destruction.

It is at that moment that Mordek reveals himself. He controls all in the Citadel, including the destructive Colossus, which attacks Wulf and the members of the caravan. As they battle their way to safety, Modeo triggers a self-destruct mechanism on the Colossus. The explosion will decimate the Iron Citadel.

Modeo leads Wulf and his allies to a secret portal that leads them to the roof of the Citadel, where a gondola awaits them. The gondola takes them to safety as the Colossus explodes, completely obliterating the Iron Citadel.