In 2013, a signal was detected from outer space. While garbled, scientists managed to discern some of the content, that the Earth would "soon have visitors." It was hoped the aliens would be wise and benevolent, but after many failed attempts to contact the originators of the messages, a decision was made in 2015. To ensure mankind was prepared should the aliens turn out to be hostile, the Earth Defense Force would be formed, a global military representing all of humanity. ...until seven years later, on June 28th of 2025 when, without warning, Ants suddenly emerge in a city.