The Bronze Saints reach a snow-covered land, which causes Yuna to reminisce about her days as a Saint apprentice and her mentor, the kind Peacock Pavlin. Sensing her mentor near, Yuna rushes to her encounter, only to realize Pavlin's allegiance is to Mars. Disciple and master engage in a fierce duel, later Yuna realizes it was Pavlin testing her, as her mentor reveals she is truly loyal to Athena Saori, and informs Yuna she is still alive and being held hostage by Mars. As Yuna prepares to rejoin her fellow Bronze Saints, both female Saints are surrounded by traitorous Silver Saints. Pavlin stays behind to cover Yuna's escape, seemingly losing her life.

Eden takes Aria away, and Aquila Yuna and Pegasus Kōga resume their journey, demoralized by their failure to protect their friend. Along the way, Yuna and Kōga separate, meanwhile Eden and Aria reminisce about the happy days they shared during their childhood. Kōga later meets a young man who first mocks his weakness, luring the teen Saint into a fight. Kōga later realizes the man to be the owner of an immense Cosmo, and turns out to be Cygnus Hyōga, one of the legendary Saints who protected Earth from great menaces many years ago. Hyōga manages to teach Kōga that to reach the true potential of his Cosmo, he must first believe in himself. After learning Hyōga's lesson, Kōga rejoins Yuna and both resume their way with renewed resolve.

Souma and Sonia are entrapped in an illusion of their past when Souma's father Southern Cross Kazuma was alive. Sonia is revealed to have been ordered by Medea to kill the Silver Saint for he was an open leader against the Martians. Hesitant on her mission she departs and faces Kazuma, as Souma also witnesses the past event. Sonia is first easily pushed away by Kazuma who tells her that her fists are made to protect those she care for, but when she thinks of her family, Sonia bursts into a rage and stabs Kazuma from the back. It is revealed then that after the murder,...

After Cancer Schiller's defeat, the Bronze Saints prepare to proceed further into Sanctuary. Meanwhile, Orion Eden reminisces about his late friend Aria. The grief-stricken Bronze Saint begins to question Mars' motives and their legitimacy, going as far as to challenge his master Leo Mycenae because of his loyalty to Mars. Mycenae and Eden engage in unequal combat to prove their conviction.

Souma and Sonia, who has been given the Scorpio Gold Cloth by Medea, engage in their long awaited final battle at the Scorpio Temple.

Kouga finally reaches Mars' location, determined to stop him. As the War God deflects his attacks and counterattacks, Eden arrives in time to save Kouga. Mars then reveals to the true story from the days when he was known as Ludwig, a normal human who sought revenge for the death of his beloved wife, Misha. He deflects Eden's attacks before removing his mask, revealing himself as a human no longer.