The Xanthos was designed as a massive armored machine capable of taking on large numbers of forces. The armor of the Xanthos made it impervious to small arms fire, however its weapons systems were exposed. In addition, repairs necessitated that the machine's critical operations and fueling systems were exposed. It had the ability to power multiple weapons systems, including a vulcan blaster, railgun module, flamethrower module, a fighter bay capable of launching air superiority fighters, and a missile bay. The machine also had a final secret transformation mode, which was able to launch a thermal laser capable of carving through large swaths of opposing forces. The inside of the vehicle is capable of housing a large number of personnel.
The Xanthos was designed at the Cerros Shipyards, and its construction was kept secret from all but the highest ranking Terran Dominion personnel. During the Defenders of Man Insurgency, it was seized as a desperate last ditch effort by the Defenders of Man and their leader, the traitor Dominion general Carolina Davis, to harm the rule of Emperor Valerian Mengsk. Davis sought to use the Xanthos to destroy the Gorgon-class battlecruisers in drydock in the shipyards, thus eliminating Valerian's ability to control the Dominion with his fleets.
However, the Xanthos was met with resistance through the Dominion forces of Admiral Matt Horner and Agent Nova Terra with her Covert Ops Crew. The Dominion was able to push back the Xanthos before it could do too much damage, and assault it as it was being repaired. As a last ditch effort, Davis activated the Xanthos's secret transformation mode, but it was not enough, and the Xanthos was defeated. Nova then infiltrated the Xanthos's wreckage and assassinated General Davis.
The Xanthos serves as a boss in the level "End Game" of Nova Covert Ops. After a short period, the Xanthos will move to one of the Gorgons stationed around the map and attempt to destroy it. While the Xanthos itself is invulnerable in this state, the weapon systems it has are not. The Xanthos has four, a flame thrower that does extra damage to light targets, a rail gun that does heavy damage against armored, a fighter bay that produced a swarm of air drones, and a missile pod that does heavy damage to an area (highlighted in red) for a short time but can be dodged. The main attack of the Xanthos, the vulcan blaster, is only used against the Gorgons.
The flamethrower also deals splash damage and each hit applies a stacking burning effect dealing increasingly higher damage over time. This effect wears off after 3 seconds of not taking any hits from the flamethrower.
The rail gun also ignores armor and each hit applies a stacking effect that increases damage taken from the rail gun by x1.2 per hit, causing the rail gun to deal exponentially higher damage as long it continuously attacks the same target. This effect wears off after 6 seconds of not taking any hits from the rail gun.
The quickest way to down the Xanthos in this stage is with battlecruisers, as their yamato cannons can outrange the Xanthos and take out one or two of its bays it can attack back. Nova with snipe can also do significant damage to the machine.
After taking damage, the Xanthos will go back for repairs, where it will be vulnerable. However, once the Xanthos gets to 75%, it will activate a new mode where it will launch beams of energy in a line at the player's forces. This can be dodged by the player's forces. The Xanthos will also call in reinforcements to aid it as it takes damage in this stage.
- Xanthos is the name of a city in ancient Lycia.
- The tooltip for the Xanthos's second form beam attack names it the "Death Laser." In the editor it is named the "Musashi Beam" a reference to the second Yamato-class battleship the Musashi.