Defend the World

As time goes by, technology changes with each passing day. Alien visitors are no longer just rumors. They disguise themselves as humans and lurk among the crowd. They have been conducting reconnaissance and infiltration for many years, spying on all intelligence. Our homeland is being watched with eager eyes. A full-scale sneak attack war has already begun. In the face of alien invasion, will you stand up and protect all living beings like your ancestors a hundred years ago? Defeat the alien forces, and the earth will win——!