Part 1 As winter arrives,
Momo Kawashima is determined to find Ōarai Girls' Academy's missing ninth tank. However, news travels throughout the school that Momo has not been accepted by any universities, resulting in a misleading rumor that she might be held back.
Miho Nishizumi and her friends figure that they can get Momo accepted into the same university as
Anzu Kadotani and
Yuzu Koyama if they can demonstrate that Momo is skilled at
Sensha-dō. To achieve this, they name Momo as the commander of Ōarai's tank teams and join the Winter Continuous Track Cup. Anglerfish Team travels below the aircraft carrier's deck to find the tank and wins the challenges set by a delinquent group led by
Ogin. Learning of Momo's predicament, Ogin's group decides to join them, forming the Shark Team, to repay their debt to Momo for saving them from expulsion. They also recover the missing
Mark IV tank being used as a
smokehouse. Ōarai faces off against BC Freedom Academy at the start of the tournament.
Yukari Akiyama learns through surveillance that the BC Freedom students are deeply divided between the original students and the high school transfer students, with their commander
Marie seemingly oblivious of the situation. Confident that BC Freedom lacks the teamwork for a coordinated defense, Ōarai undertakes a direct attack on their flag tank. However, BC Freedom demonstrates an unexpected
esprit de corps and traps Ōarai in a crossfire on a bridge. Ōarai uses Shark Team's tank as a makeshift bridge to escape. BC Freedom and Ōarai retreat following the failed ambush.
Part 2 After escaping BC Freedom's ambush, Ōarai uses Mallard Team's
Renault Char B1 and the cover of a
bocage's hedgerows to pose as a BC Freedom tank and reignite the quarrel between their students. Exploiting their opponent's temporary confusion, Ōarai takes out Marie's flag tank and wins the match. While on a break before the next match,
Saori Takebe accompanies Momo to her home and meets her four siblings and her frail mother. Meanwhile, Chihatan Gakuen, Pravda Girls' High School, Saunders University High School, Kuromorimine Girls' High School, St. Gloriana Girls' College, Anzio Girls' High School, and Keizoku High School advance to the next round. Ōarai's next opponent is Chihatan, which adapts a new set of effective tactics that they learned from Ōarai's examples. Chihatan uses hit-and-run attacks and amphibious assaults to launch numerous ambushes on Ōarai, but the latter forces their retreat after luring them into a trap.
Part 3 After regrouping, Chihatan resumes its hit-and-run attacks on Ōarai. Chihatan's commander
Kinuyo Nishi decides to focus on taking out Anglerfish Team to destroy Ōarai's morale. Ōarai tank teams quickly become separated in the confusion and multiple skirmishes take place. Miho decides to turn on her tank's headlight to expose her location and draw all of the Chihatan tanks towards her. As Chihatan celebrates after disabling Anglerfish Team's tank, Turtle Team, Ōarai's flag tank, comes out of hiding and disables Kinuyo's tank, winning the match in the process. In other matches, Kuromorimine defeats Pravda after
Erika Itsumi followed
Maho Nishizumi's advice and used her tactics that diverge from the school's traditional frontal attack, St. Gloriana easily defeats Anzio, and Keizoku manages to pull an upset victory against Saunders. This leaves Ōarai to face off against Keizoku and Kuromorimine against St. Gloriana in the semifinals. At the outset of the third match, Keizoku uses hit-and-run attacks and guerilla tactics against Ōarai, splitting their forces as a result. As Anglerfish Team protects the Anteater Team, their flag tank, one of the Keizoku's tank team, commanded by the one known as the "White Witch", disables Miho's tank with a single long-range shot.
Part 4 The quick elimination of the Anglerfish Team sinks the morale of Ōarai and sends shockwaves to viewers of the game. Anzu takes an impromptu role as commander to keep the team from falling apart and has their tanks protect the Anteater Team by digging trenches in the snow. After discovering an abandoned underground aqueduct for escape,
Azusa Sawa takes over as the new commander when the Turtle Team's tank is taken out by the "White Witch",
Jouko. Sawa leads the Ōarai tank teams to weed out Jouko and eliminate her, through baiting tactics. With Sawa's commands, she allows Ōarai tanks to outnumber Keizoku's flagship tank,
Mika. However, Mika lures them into a trap, causing both Keizoku's and Ōarai's tanks to plunge down the side of a mountain. As the two teams fight, while sliding down the mountainside, an avalanche takes out all but the Anteater Team and two Keizoku tanks, including Mika. Keizoku chases Ōarai into a village, where they are tricked by a diversion allowing the Anteater Team to eliminate Keizoku's flagship tank and win the match. Meanwhile, Kuromorimine and St. Gloriana face each other in the semifinals.
Darjeeling overwhelms Erika, by spreading Kuromorimine's teams apart. Before St. Gloriana can corner Kuromorimine, a sandstorm allows Erika to regroup and bring the match to an even playing field. St. Gloriana then introduces their new transfer student,
Alice Shimada, who enacts a decisive blow on Kuromorimine and wins the match, deciding the final match between St. Gloriana and Ōarai. == Cast and staff ==