Eagle City, Komerica -- WNA Research Laboratory Branch

WNA researchers Burton, Berecca, and Ron continue their tireless efforts to develop "Ninja-Gum"; a mysterious substance that activates latent Ninja DNA in people descended from those legendary mercenary warriors (alt: those legendary mercenaries from days gone by). Today, all their hard work finally pays off. It is here - on their 2,503rd attempt - that they finally succeed in producing Ninja-Gum! Burton and Berecca can barely contain their excitement, and waste no time in trying the gum for themselves! But then...
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(Source: Official YouTube channel)