After returning from his mourning solitude and soul searching, a raging Yogostein is convinced to rely on his very own power as he goes all out into pouring it into the creation of destructive Hammer Banki to extract his revenge on the Go-ongers. After a failed attempt to work on the newest weapon he and Jum-bowhale have been developing, Hiroto takes a break until Hammer Banki begins his attack. Finding the district in ruins, the Go-ongers encounter Yogostein as he has Hammer Banki attack them before the Go-on Wings arrive. However, Go-on Silver is gravely injured in the fight when she attempted to save her brother from Hammer Banki, with Go-on Gold forced to watch his sister being brutally wounded further until the Go-ongers intervene and Yogostein retreats to re-energize his monster while the other Pollution Ministers express concern for their comrade's state of mind. With Miu on life support, Hiroto vows as he trains himself with the male members following him to talk him to be at his sister's side while learning that the training is for something else that can destroy Hammer Banki. Once Miu regains consciousness, she and Jum-bowhale reveal the project Hiroto has been working on, the Go-Roader GT, though without a working Power Soul is prone to attack everything. As Renn decides to solve the Power Soul issue with Miu's aid, Hiroto arrives to face Yogostein and Hammer Banki, attempting to use the Go-Roader before it started to attack him. However, the other Go-ongers arrive to hold the Go-Roader off so Hiroto can deactivate it. Though Yogostein decides to retreat at the moment, Hammer Banki refuses to run off and enlarges to kill the Go-ongers and his master until Jetras and Bus-on arrive and the teams form Engine-Oh G9. Once formed, Renn gives Hiroto the completed T?kon Soul to use on the Go-Roader, enabling it to enlarge and assume Action Mode to weaken Hammer Banki before it and Engine-Oh G9 scrap him. As Kegalesia and Kitaneidas comfort Yogostein as he realized the downside of his vengeance, the Go-on teams celebrate the Go-Roader's completion as Hiroto gives the new weapon to the Go-ongers after they prove themselves in a group jog.