group discover that it utilises both new technologies as well as three of the world's bending styles, making it the first joint business venture between nations in the Avatar world. Aang becomes concerned that a nearby river has been polluted by the refinery, and continues to see visions of Yangchen, which convince him of impending danger resulting from the refinery's construction. When Aang tries to voice his concerns, an argument starts between him and Toph; Aang is upset that the refinery and town have been built on sacred ground, while Toph, impressed by the innovations, multicultural nature and prosperity of the refinery, has no issue with its presence. Furthermore, she dismisses Aang's warnings about his visions on the basis that he does not know exactly what is going to happen. When Aang points out the nearby pollution, Toph confirms Satoru's claim that the refinery is not responsible, causing Aang to suggest Toph is lying to protect her crush. The argument is brought to a stop when a series of earthquakes threaten the lives of the refinery's workers, and prompts Aang and Toph to work together to prevent anyone from getting hurt and minimize damage to the refinery. After the danger is over, Toph suggests that Aang is trying too hard to hang onto the past, prompting Aang to suggest that Toph is trying too hard to run from it, to which Toph claims that she has no choice. At that moment, the refinery's owners—Satoru's uncle Loban, and Toph's father Lao Beifong arrive on the scene, and the novel ends with Toph and Lao recognizing one another. Part Two Lao claims that Toph is not his daughter, and tries to have her, Aang and their friends escorted out of the refinery. After a battle with the Rough Rhinos, a group of former Fire Nation soldiers now serving as the refinery's security, the group go their separate ways; Aang, originally intending to confront Lao and Loban about the refinery's construction, is persuaded by the Air Acolytes to continue celebrating Yangchen's Festival. Toph resolves to confront her father, while Katara and Sokka decide to explore a hidden cave unveiled during the battle. Traveling through it, they discover that it leads to an underground iron mine, which is revealed to be the source of both earthquakes and pollution. During a ceremonial meal, Aang is able to contact the spirit of Yangchen, who reveals that