As Bagramon proceeds with the Day of Ultimate Destruction, Taiki and Mervamon find themselves trapped under the Great Bagra Palace. There they discover Yuu, but a new enemy stands in their way when they attempt to save him. Meanwhile Kiriha watches as DarkKnightmon forcibly fuses with Bagramon, creating an immensely powerful DigiXros that destroys whole realms and all the data in them. Is it too late for Taiki's team to stop D5?!