The X-Ray Laser was developed by the Thebans, who, lacking Force Beam technology, pressed further with laser development than other races. Other races developed X-Ray laser buoys for warp point defense, but as these required a nuclear detonation to fire the weapon and destroyed the buoy after one shot, X-ray lasers were never considered for starship use. The Thebans got around this problem by exploding nuclear weapons in massive, armored detonation chambers in their capital ships. Shielded conduits direct some of the explosive energy to X-ray laser projectors. The result was a powerful ship-based laser system that was only matched when the Terran Federation developed the Hetlaser.
The advantage of the X-ray laser is that, like other laser weapons, it ignores shields and is resisted only by a vessel's armor. The disadvantage is that a malfunction in the firing chamber can conceivably destroy the firing vessel.
Like most beam weapons, X-Ray Lasers cannot penetrate the atmosphere of a planet.