ThunderGun: The Cybwar Mission (1997)

The year is 2880. For the past century, extraterrestrials have been pillaging the planet Soran for its massive deposits of Asterite, a light-weight anti-gravitational rock used to build stable orbital cities. Galactic wars have been fought between the different life forms excavating for the valuable rock. As a Thunder Gun pilot, your mission is to journey deep into Gateway's underground lair to defeat his robotic army, free the kidnapped Queen, and deliver Earth from the grip of this brutal cybwar.