Imperial Fists Chapter Master Korico Justonmund stands on the bridge of Phalanx. The legendary mobile fortress-monastery of the chapter hangs in orbit above Terra. When not taken away by chapter missions of vital importance, it serves as the flagship of Terra's Defense Fleet. The size of a small moon, it is the largest vessel ever known to be crafted by mankind and goes back to the Dark Age of Technology. However, like so much else in the modern-day Imperium, it is decaying. The Phalanx was meant to hold a full Space Marine legion of over ten thousand. Since the Horus Heresy and the sundering of the legions into chapters of a thousand or less, the mighty vessel has rarely ever seen that number walk its halls. Chapter Techmarines and surfs do what they can to keep the ship going, but they have to focus on the vital sections while the rest of the ship is left to wither in the dark.
Korico is wearing his full battle plate as he sits on his command throne, going over reports. The bridge is tiered, and his throne sits above that of the Phalanx's commander, Captain Agal Lazado. Korico looks up from a report when an alarm sounds. Korico stands and descends from his throne. The bridge is suddenly buzzing with activity. Agal moves to meet his Chapter Master.
"The Palace has been put on Ultax alert," says Agal, passing Korico a data slate, "At first, I thought it was the Custodians conducting another of their Blood Games, but the signifier is that of Captain-General Aecar Arshenzo, and it is coded as real. There is an intruder in the Imperial Palace."
Korico takes the slate and reads the report. He can't blame his brother for thinking it is a Blood Game. The Custodians conduct them all the time. Sending one or more of their number outside the Palace and having them break in to test the defenses. They do not always inform the Fists of these tests, but the brothers who man the walls always enjoy testing their skills against their golden cousins. They rarely win, but losing to one of the Emperor's guardians is never anything to be ashamed of.
The message in the slate is sanitized and straight to the point. An intruder or intruders has entered the Palace. The Custodians have moved to eliminate whomever it is. The Phalanx and the rest of the Terran fleet already know their roles in this situation.
"Start scanning full power for any ship that doesn't belong," says Korico as he passes the data slate back to Agal, "Send out a message to all vessels-"
Ten faceless silver figures taller than an average Space Marine appear around the bridge. Korico, Agal, and every other Imperial Fist on the bridge draw their weapons without hesitation. The human crew is not far behind. They are all armed with sidearms, but they all draw their close-quarters weapons as they have been trained I do in sensitive areas like the bridge. Guns would only be drawn in the most dire circumstances. Korico powers on his two-handed power sword and points it at the nearest silver giant.
"I do not know who you are-" the sound of a machine scream cuts off Korico.
He turns and sees that one of the silver giants has one of the bridge tech priests by their head. With almost contemptuous ease, the silver giant crushes the priest's metal skull before tossing the robed corpse aside like trash.
"Kill them!"
Korico follows his order by charging the one he was addressing and swinging his blade for its head. The thing catches the blade barehanded, grips it, and with strength like Korico has never seen, swings him bodily around, using him like a mace to bash Agel, who was coming at it from the side to the ground. It continues the spin, releasing the blade and sending Korico flying into another brother. Both go down hard. Korico gets back to his feet fast and looks around the bridge, seeing that know of his men are fairing any better. Whatever these things are, they are faster and stronger than Space Marines. What makes it worse is they are all barehanded. Not one of them has a weapon.
It only takes him a few seconds to comprehend this. When he looks back at his opponent, he sees Agel charge in from behind with his power sword aimed at the things back. The silver giant turns just in time to be stabbed through the neck. But something is wrong. The blade doesn't cut through. Taking the thing's head off, it stops. Stuck like an axe in a solid tree. Korico watches Agel pull, but the sword doesn't move an inch. The silver giant grabs Agel by the arm and proceeds to swing him through the air like a rag doll, slamming him into the floor over and over. Ceramite cracks, and Korico is sure that Agel's reinforced bones do as well. The silver giant throws the Space Marine like a broken toy across the bridge just as the bridge doors open, and two members of First Squad in full Terminator Armour step in just in time for Agel to hit one of them full in the chest and be knocked backward.
"To the Warp with this," roars Korico as he pulls his plasma pistol, "Open fire!"
He aims the plasma pistol at the silver giant as it pulls Agel's power sword from its throat. Korico watches as the silver flows like water over the wound, repairing it. The pistol hums with chained power, and Korico pulls the trigger. The green ball of energy hits the silver giant full in the chest, bathing it. Korico killed Traitor Space Marines and armored vehicles alike with this weapon. Nothing walks away from a direct hit from it. Well, nothing until now. The silver giant, now with a hole melted into its chest showing, nothing. There is nothing under the silver, just space.
"By the Emperor," says Korico as the silver giant moves toward him, "What kind of abomination are you?"
He doesn't get an answer or a chance to get a second shot. In fact, he is the only one who got a shot off at all. The silver giants get serious, moving like blurs over the bridge, smashing the Space Marines in their human surfs to the ground. Even the Terminators are beaten and broken, ripped from their heavy armor, and left bleeding with their brothers. The tech priests are not so lucky. The giants show them no mercy, killing them without a second thought. This continues throughout the Phalanx until, for the first time since it was claimed by Rogal Dorn and entered service to the Imperium of Man, the legendary home of the Imperial Fists has been captured by an enemy force. The same thing happens to every ship in the Terran Defense Fleet in orbit around humanity's birth world, and all within one hour.