When Prism Tower awakens and the Ultimate Weapon hidden beneath Lumiose City is activated, chaos erupts across Kalos. As rogue Mega Evolutions spread throughout the city and thousands of lives are put at risk, Y/N and Urbain are forced to make an impossible choice. Both are willing to risk everything to stop the disaster, leading to a battle between them over who will accompany Floette into the heart of Prism Tower. Y/N wins. Urbain goes anyway. Separated by the crisis, Urbain descends into the tower alongside Floette while Y/N remains above, racing across Lumiose to protect civilians, battle out-of-control Mega-Evolved Pokémon, and hold the city together as it threatens to tear itself apart. With the fate of Lumiose hanging in the balance, Y/N and her Pokémon push themselves beyond their limits. But as the fighting intensifies, injuries begin to mount—and Y/N becomes so focused on saving the city and ensuring Urbain's survival that she never realizes just how badly she's been hurt. As the final battle approaches, Y/N joins forces with Zygarde to confront the Ultimate Weapon itself in a desperate fight for the future of Lumiose. The city can only be saved once. The people she loves can only be protected once. And Y/N is willing to give everything she has to make sure they survive. Even if she doesn't.