From publisher blurb: Welcome to the Vega system. Tyrannical aliens from a world much like our own have conquered the majority of the system. Using the mysterious element 122, which can be refined from ordinary sea water and which powered their spaceships in interplanetary flight, these aliens then developed a hyperdrive and discovered the solar system. Earth was the next planned conquest. Already, they walk among us and recruit criminals to help prepare the Earth for conquest. However, rebel aliens from conquered worlds made their way to the solar system, to both warn the people of Earth and seek help against their overlords. The scientists, engineers, pilots, and soldiers of the Invisible College are their Terran allies, who keep news of the impending alien invasion secret, to avoid both mass panic and to not alert the aliens who walk among us. In Rocket Rangers you can: Fight the criminal gangs allied with the evil aliens, both in the skies and on remote portions of the globe. Capture or destroy alien rockets and bases within the solar system Fight the alien invasion of Earth Take the fight back to Vega system, and help humanity's alien allies free themselves from their tyrannical overlords. Requires the d20 Modern Role Playing Game published by Wizards of the Coast