The linchpin of the Kilaakian invasion plan, the Monster Control Device allowed the alien race to gain complete control over earth's kaiju. Adapt at mind control technology, the extraterrestrial race would resort to surgical insertion of these devices into humans to control them. In rare cases, the devices were placed outside the body, such as in place of jewelry like earrings.

For the Earth's monsters, however, a more elaborate plan of control was enacted. Rather than attempting to surgically insert them, which could prove both dangerous and also challenging since their outer skin can withstand traditional firepower, an outside source of control was used. Located on their moon base, a central Monster Control Device was established. From this central device, all of earth's kaiju would be bent to the will of the Kilaak. To carry this out, the alien race strategically placed transmitters on planet Earth. Located all through out the world, each transmitter permitted the central unit on the moon to control the targets as long as they were within at least 2,000 kilometers of it.

With their network of transmitters in place, the alien race started their campaign for conquest. First, Monsterland on Ogasawara Island was invaded. The monsters and humans were gassed, incapacitating both long enough to surgically control the human staff and utilize their Monster Control Device on the kaiju. With the island secured, the monsters were dispatched all over the world to cause massive destruction, with Godzilla sent to New York, Rodan to Moscow, Gorosaurus to Paris, Manda to London and Mothra to Beijing.

The plan goes accordingly except for one flaw: the transmitters begin to be discovered on Earth. While well hidden, such as disguised as a rock or stashed in a chapel, the transmitters are ultimately unguarded. Through a combination of luck and determination, after the first ones are uncovered, the transmitters are gradually gathered up. However, one more step is needed to stop the main assault, and that is to severe the main Monster Control Device.

For this mission, the Moonlight SY-3 space craft is dispatched to the moon and uncovers the Kilaak moon base. After escaping the fire trap at the entrance, and blowing out the door, the crew of the craft break into the alien fortress. There they find the Monster Control Device, although well protected. Ultimately, the crew uses one of the laser cannons on their Exploration Car to burn through the base of the Monster Control Device, severing the aliens control of Earth's monsters. With the device in the hands of humanity, it was time to reverse engineer the technology and take control of the kaiju to defeat the Kilaaks.