After Kotori comments on the success of Ratatoskr arming the buildings of Tengu City with hidden weapons, the Spirits are deployed to the battlefield. As everyone else scatters to perform their roles, Miku and Natsumi stay behind to boost the strength of everyone else with March. Ryouko and the AST squad also arrive as the war begins, growing even more conflicted as DEM Wizard Irene Fox deliberately uses them as friendly fire against the Spirits. After being saved by Yoshino and Mukuro, Ryouko is convinced that Origami's warning is correct and tells her team to prepare for re-employment.

Elsewhere on the battlefield, Origami is confronted by Artemisia, who rejects Origami's suggestion that DEM has brainwashed her due to those words coming from a Spirit. Despite Artemisia being betrayed by the AST team she had expected as reinforcements, she still manages to parry Origami's blows and injures the Ratatoskr Wizard's flank. However, this ends up serving as a second distraction for Mukuro to sneak up and unseal Artemisia's memories with Michael.

In a separate Ratatoskr airship, Woodman sees from the monitor that Ellen has been dispatched to the frontlines. Knowing he is the only one available capable of intercepting her, he stands up and prepares to use his CR-Unit again. His assistant Karen admits she is in love with him and jokingly suggests that they should perhaps flee from the battle and start a family someplace else. Woodman politely turns her down, complimenting her humor before leaving for the battlefield. Equipped with his golden CR-Unit which restores his youth to its prime, Woodman casually greets Ellen, asking if she enjoyed the title of being the strongest Wizard without him being present. Woodman's presence causes Ellen to lose her composure, howling in fury as she advances to attack.

While chasing after the Nibelcole who are fleeing, you reunite with the original Kurumi, who still wants to absorb your Reiryoku, so she can change history to prevent the birth of Spirits in the first place. As the two simultaneously deal with surrounding Nibelcole, you argue that Kurumi has no guarantee that changing history will work, which Kurumi refutes that she doesn't want to hear those words from someone who has already changed history for the better. Still, you don't want that to happen since altering the past in this manner would change things so that you never met Kurumi. You propose that you confront the Spirit of Origin in Kurumi's place, sealing her to rewrite history and ensuring a happy future for everyone.

Kurumi finally concedes, admitting that you have won their wager, and she is willing to let you seal her power after this war concludes. However, before you can celebrate, Kurumi screams in agony as a hand emerges from her chest. You can only look on in horror as the hand extends outward to reveal a mysterious person.

Kurumi is left mortally wounded after Mio Takamiya fully emerges from her chest. After firing one last Zafkiel bullet that seemingly misses, Kurumi warns you one last time before collapsing to the ground. "Run..."

With her Astral Dress and remaining clones vanishing to indicate the end of her life, Mio approaches Kurumi's body. "I apologize Kurumi Tokisaki. Also I thank you for being my friend until the very end." Then she closes Kurumi's eyes as a sign of respect.

Sensing your confusion and horror, Mio restores your memories as Shinji Takamiya to have you remember everything. Back on Fraxinus, the crew is left shocked over Kurumi's abrupt death. However, Kotori is more disturbed by Mio's stark resemblance to Reine. Despite wanting to treat the similarity as just a bad joke, Kotori is forced to give MARIA the command to electrocute Reine's console due to the analytic officer's eerie silence. However, Reine merely stands up unaffected by the electrocution. "Thank you for what you've done for me. Thank you for protecting Shinji all this time. Though I must say I'm impressed you're this smart Kotori for figuring it out yourself. But it's now over."

Reine then teleports to Mio's location, with the two of them merging back together into a singular entity with an ethereal Astral Dress equipped. Mio is overjoyed at them finally being reunited, but you have reservations about the number of sacrifices made to bring back Shinji Takamiya. Mio questions what alternative she had since she is simultaneously not weak enough to die but also not strong enough to move on from him. You are left unable to reply, so Mio decides to erase your guilt along with your memories. However, before she can do this, you are pulled back by Tohka and the Yamai Twins, who have all been briefed on the situation. Mio sends you away from the battlefield while resolving to eliminate the other Spirits to retrieve their Sephira Crystals.

Having finally collected all of her Sephira Crystals, Mio approaches you, the last obstacle to her perfect reunion with Shinji.

"I've recovered all the Sephira. Along with their lives. Now we can be together forever."