A Xon maintenance drone is a large hollow sphere about the size of a small moon. Its surface is studded with launch tubes to such an extent that the gigantic craft looks more like a prickly sea urchin than a moon. Despite its ominous appearance, the drone has no offensive weapons capabilities whatsoever. Unless, of course, you count the 400 billion terra-formation capsules nestled inside its hollow shell as offensive weaponry. The Xon, it should be noted, did not consider the atmosphere seeding devices to be weapons of any kind. Granted, Phase II of Project Designate 3495985340 had caused such drastic climactic changes that it had wiped out most of the dominant reptilian species on the planet at that time, but the Xon were not cruel, several specimens had been preserved for later use.

The drone's only defensive capability was to flee in the face of adversity utilizing an inter-dimensional portal generator buried deep within the craft. This amazing device basically allowed the drone to shift in and out of normal space in the blink of an eye. Even then, the drone's jet black exterior made it extremely difficult to see with the naked eye, let alone telescopic scanners. But the backwash of the portal generator when it phase shifted is what set off the gravimetric sensor alarms aboard the Valley Forge when the Xon maintenance drone suddenly materialized about 36,000 clicks from the planet Earth.