The Nasuverse sensed a foreboding event that will happen to Chaldea; especially the Humanity's Last Master. So Nasu send and asked help from the other Thrones of the Omniverse. The first one to to take the call was the Throne of Cards. A certain King of Games, instead of him, sends someone else in his place to aid the Last Master. It's time to Duel!

The World of Heroes are not prepared for the coming of the embodiment of Evil herself, The National Executioner, Koumori Kuroko! Due to the attack of the League of Villains on U.A., The Government, instead of HPSC, decided to step in and summoned their Executioner to eradicate the League once and for all. Heroic Ideals didn't matter to Kuroko; her job is to kill because she can.