Other Title: 仮面ライダービルド-ライダーウォーズ開戦, Kamen Raidā Birudo-Raidā Wōzu Kaisen
Summary: At last the war has begun! Instigated by virtue of Hokuto through their
prime minister's actions, the Touto government officially instigates the
Kamen Rider as their military weapon. "I do not intend to become a tool
of war" Sento replies. There is a reluctance in Sento's words though,
as he realizes that the outbreak of this war was also due to him
creating the Rider System and the Smash. Just what decision will these
two warriors make?