The continuing onslaught and increasing range of the invading Mysterian forces prompted the Japanese Self-Defense Force to search for unconventional means by which to fend off the terrible aggressors. The Alpha-Class Aerial Battleships were a failure on their own, and a new technology was pursued: the Markalite Cannon! With the ability not only to reflect the deadly beams of the Mysterians' Dome but also to produce powerful rays on its own accord, the futuristic device would have the ability to wage war on the mysterious menace. The weapon was far too enormous and far too conspicuous, however, to be transported to battle by any normal means. It would need a sufficient transport ship...

Towering over twice as tall as the highest skyscraper, the vehicle that would carry the cannon into the heat of combat, the Markalite GYRO (Giant Yoked Rocket), released a blast of choking smoke and a stream of searing fire as it launched into the atmosphere. Leaning into a horizontal position, the rocket released its thrusters, allowing them to fall to the Earth below. As the Markalite GYRO approached the enemy fortress, an explosion split the gargantuan transport in two, and the Markalite Cannon drifted gently to the ground, cushioned by a modest rocket of its own. A second Markalite Cannon descended to the ground soon thereafter, and the epic battle for dominion over the planet continued in full force in the once peaceful Japanese countryside.