“We’re coming up to it now, Doc,” Hacker said as their ship drifted through space.“Excellent.” Doc Terror looked through the monitor at the planetoid. It had first shown up in the solar system a week ago and appeared to be on a collision course for Earth. While Doc Terror didn’t care about the casualties the impact would wreck on the human race when it smashed into the planet, he certainly did not want to lose Dominion, his base in the Arctic region and the predicted point of impact. After further readings, he determined the asteroid to be hollow, full of processed metal, and not just drifting through space, but creating its own propulsion. The object was no mere asteroid, he knew, but some kind of ship in disguise. A ship he planned to take and use in his conquest against the human race.“Are the Doom Drones ready for deployment?” he asked his cyborg henchman.Hacker tapped a few buttons with his one human hand and nodded.“Still no reaction from the surface?”“Negative. And no life-signs from within it. What if there’s no one inside?”“Then the easier it will be to take control of it. As soon as we make contact,” Doc Terror said, “send out the land forces to break through the surface.”As the Shadow Star cruised through space towards the Earth, Umbra acknowledged the lime green ship coming close to it and dismissed it just as quick. If it wasn’t the Mighty Orbots, Umbra determined it to be no threat. Once the ship landed on the outside of his space-faring base, though, the massive supercomputer reconsidered.“Perhaps, the Galactic Patrol has come to surrender,” Umbra mused, as the holographic image from the surface that filled the Star Shadow morphed into the multi-eyed projection Umbra had adopted. The theory quickly died as a massive robotic force spilled out from the ship and began working on drilling through the hull of his fortress. “Fools, attempting a frontal assault on Shadow Fortress will be your undoing!” As the Shadow Star had no exterior defenses, Umbra began amassing his Shadowbots at the invading force’s entry point.The drone force broke through the surface, small at first as drilling robots fell through the breach, then a stream of jet-like robots flew through and spread out to search in interior. Umbra’s flying Shadowbots, looking more biological with pointed heads and long flapping wings, engaged the invaders, streaking after them and firing laser blasts from their eyes. Even as the interloping robots were blasted out of the sky a second wave flew in through the expanding hole in the Shadow Star’s surface.Lasers filled the expanse, joined in by missiles fired by the drones. Advanced targeting systems in the projectiles found target after target, blowing Shadowbots out of the sky. In the middle of the carnage, the invader’s ship lowered into the Shadow Fortress and found purchase on a metal-plated plateau.“Shadowbots, destroy the ship!” Umbra ordered, his voice echoing within the Shadow Star. More robots – these resembling steel pumas – pounced on the ship and began ripping its hull to pieces.“Deploy the Traumatizers!” rang out from within the ship, and a platoon of humanoid robots poured from the ship, lasers firing from their arms and face monitors. The two robot armies tore into each other until the Traumatizer robots flipped over and fired a volley of missiles from their torsos. The ordinance took out Shadowbots in waves as they advanced on the ship, but the Shadowbots kept coming and the invading army dwindled like rocks against a current.Above it all, Umbra’s visage watched in satisfaction. When the assault has been repelled, Umbra would enjoy watching the leader shredded by his Shadowbots.“Our Doom Drones are getting destroyed out there, boss!” Hacker shouted, watching a Traumatizer’s head being bitten off by a cat-like robot. He shot at it from the metal mace on one end of his robotic arm and ordered another Traumatizer to take its place.Doc Terror slid a rocket into his cybernetic arm’s barrel and launched it at a group of robots, blasting them to pieces. He looked out at the expanse, filled with broken and deactivated robots. “Start the portable cyborg-making machine; I’ve got an idea.” He commanded a second squadron of Doom Drones, six-wheeled robots built for speed and maneuverability, to find the Shadowbots that still functioned and bring them back to the ship. “We’ll turn that hologram’s forces against itself!”Hacker flipped an array of switches in the ship’s cargo bay lit up, shining light at the mechanical orb. The top half of the machine rose up on stilts. The biggest technological feat of Doc Terror, the cyborg-making machine was capable of turning any creature into a cyborg, increasing its strength, adding loads of firepower and most importantly, putting them solely under Doc Terror’s control.The Doom Drones retrieved dozens of robots as they tried to fight back and tossed them into the open half of the machine. Doc Terror switched on the machine, closing the machine and infusing the machine with light and cybernetic energy. When the machine opened again a few moments later, twisted metal robots emerged, multiple Shadowbots merged together to form a powerful dragon-like Borg, awaiting orders.Doc Terror examined the robot with pride as a pair of Shadowbots broken into the ship. “Take them out!” Terror shouted, gesturing at the intruders. The Borg launched itself at the Shadowbots and ripped one to pieces with its massive claws, then jumped at the other and coiled around it until the Shadowbot was crushed to death. “Perfection!” Terror said, “Hacker, begin mass production!”The machine closed on pile after pile of pulverized Shadowbots and rose again, each time creating a different combination of robot parts, each one more devastating than the last. The hologram projection floating in the sky could do nothing more than watch on as his forces were turned into metal monstrosities and betrayed him. As the metal abominations spread through the Shadow Fortress and ripped the remaining Shadowbots to shreds, Umbra had one final option: Destructitron.Bay doors opened, spilling robotic corpses into gigantic robot’s lair. Rockets ignited, carrying the automaton into the air, where it loomed over the invading force’s ship. It took the craft into its monstrous claws, preparing to tear it in half, but the combined number of the mangled former Shadowbots overwhelmed the Destructitron, devouring it in a swarm of fangs and claws. Umbra’s last line of defense was gone, and nothing stood between his data banks and the invaders.Umbra’s projected face flared in the hollow planetoid as the red and blue cyborgs crossed the expanse to the interior of the Shadow Fortress. “Do not go any further!” he shouted.The red one looked up at him and sneered. “Doc Terror goes where he wants!” He placed a claw-like weapon into the barrel on a mechanical arm and gripped the entry door before pulling it clean off its hinges. Inside, he found the gleaming computer array that made up Umbra’s neural network.“You’ve fallen into my trap,” Umbra said with a deep, grating laugh. “You’re within my mind, where I rule all.” The computer systems melted away, replacing the intruder’s vision with a view of a scorched Earth. Dominion lay open and ruined, where the full weight of the Shadow Star had impacted, wreaking havoc on a global scale and ending all life on the planet. The blue cyborg dropped to his knees and cried out at the prophetic imagery, but the red one stood firm.“Enough of these tricks!” he yelled, unloading a barrage of lasers around him. The blasts flew harmlessly through the illusion, but found their target at the hidden computer network. As the systems that made up Umbra deactivated, the hologram of Earth’s destruction shimmered away. Umbra’s face flashed once more in the Shadow Fortress then faded from sight, with the cyborg’s maniacal laugh the last thing the supercomputer registered before going offline forever.
Both Umbra and Doc Terror had access to huge robotic armies, but only one of them showed a capability to create new ones. Umbra's forces don't show an origin, so we have to assume he'd either had created them a while ago or had them brought in. Considering Umbra doesn't really show any capability of building them himself - he even needed others to build stuff within the Shadow Star and operate them. Doc Terror, on the other hand, has a cyborg-making machine, and has been able to build himself an army in mere hours. I might have fudged it a bit since the fodder for the machine was robotic and not biological, but a. the Shadowbots looked plenty biological to me and b. how hard would it be to add robotics to more robots instead of animals? I'm also assuming as easily as the Shadowbots were able to overwhelm Mighty Orbots in the beginning, that a bunch of Shadowborgs would be able to do the same to the Destructitron. And lastly, the illusion in Umbra's memory unit only held back the uncertain Orbots for a few minutes - someone with the confidence of Doc Terror wouldn't have been phased by it for more than a few moments.