After the Vanguard High School Koshien ends, Kouji Ibuki starts experiencing fresh nightmares. Nome Tatsunagi orders Suiko to bring him to the manor where they discover he can perceive a Dark Tower known as Sanctuary. Sanctuary is distorting history's timeline, and the only remedy is for Kouji to amend his future error first. Thus Kouji and Suiko must journey into a parallel realm—if possible—and observe Magical Girls Emi Sendou and Shuka calling Vanguard units to restore history. Unfortunately, the pair cannot contribute much since card battles against genuine monsters prove largely ineffective. Their efforts are hampered by the overwhelming presence of ancient evils.