So the Shadowkeepers. They're a Shield-Host of the Custodes, charged with securing dark abominations and archaic technology, keeping them contained beneath the Imperial Palace in the Imperial Dungeons, and protecting Terra and the Imperium from these. Secure. Contain. Protect. m. Headcanon activate.
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Uraxes was relatively new to the Shadowkeepers. Of course, he knew what they did and held them in high regard. But for him to actually be a part of these black-armored Custodians was, well, surreal to say the least.
The darkness beneath the Imperial Palace is where they patrolled. They were the secret guardians, the jailers of that which could sow panic and terror. They died in the dark so that the light may live.
Uraxes walked through the dimly lit passageways, occasionally passing one of his shield-brothers. No one spoke needlessly here. There was no reason to. Unless more than one of the cells were breached, each Custodian could handle whatever the threat was. Uraxes had his orders. He was to relieve Shield-Brother Racandon, who had been selected to become one of the companions.
When he arrived at his destination, they formed a fist over their hearts in salute on one another.
"Is it still in there?" Uraxes asked. Racondon nodded.
"Still scraping away as usual."
"When was it cleaned last?"
"Two days ago."
"Then we may need menials to clean it." Racondon shrugged.
"It's under your watch now. If you want to order some menials to clean it, go ahead." Uraxes sighed.
"Very well. May you endure your watch with honor. Ave Imperator," Uraxes said in farewell. Raconden took his leave.
"Ave Imperator." Uraxes took his position in front of the door and began his vigil. He remained there for nearly fifty years until something happened.
Yet another menial crew arrived before Uraxes, ready to clean the inside of the cell. As per protocol, another Custodian, Shield-Brother Ayon, joined him when the door opened.
Standing still against one wall was an oddly shaped statue. It's head was many times larger than it's body. Short, fingerless arms protruded from the torso, which was supported by two legs that looked similar to the arms. Paint was smeared on it's face in an odd pattern. Uraxes felt a strange sense of unease settle over him as the menials began cleaning the floor, covered in what was found to be blood and feces from an unknown source. Uraxes and Ayon watched the statue, never blinking.
Until they both blinked at the same time.
Three wet snaps and three dead menials lay on the ground. The statue had moved unnaturally fast from it's corner to barely a meter and a half away from Uraxes and Ayon. Ayon reacted out of instinct, firing five rounds from his guardian spear. The mass reactive warheads detonated on impact, blowing craters in the stone, exposing simple metal bars underneath.
"Get out, Ayon!" Uraxes yelled turning to run outside.
Another wet snap and Ayon's body fell next to him, his head twisted to an unnatural degree. Uraxes whirled around to see the statue within an arm's reach. Uraxes fell back, shocked at the statue's speed and hostility. He'd heard of this... thing's abilities before but to see it use those abilities to slay a Custodian was shocking.
"Containment breach!" Uraxes yelled into his vox. "The statue has breached containment!" Uraxes maintained eye contact with the statue. Never blinking. The sound of numerous Custodes reaching his position sobered Uraxes. Multiple Custodes fanned out in a circle around the statue, guardian spears crackling with energy. Uraxes slowly stood, still watching the statue.
"You may relax, Uraxes." Startled at the voice, Uraxes turned to see Shield-Captain Myrikos behind him. "The death of Ayon was regrettable, but now you see why we must never falter."
"Shield-Captain, my actions caused the death of a Shield-Brother. I offer my life as yours to take or my armor. I am not fit to be among the Shadowkeepers, much less the Custodian Guard. To be beaten by a simple statue is-"
"Understandable." Uraxes looked behind Myrikos to see a normal, mortal human, shrouded in shadows. Uraxes could not tell if they were male or female, short or tall. Their voice had no identifying features of any kind and seemed almost robotic, as if whoever it belonged to had spent their life making sure their identity was a secret. "There are things that have been kept from you, Uraxes. Such as the true nature of One Seven Three. I am Oh Five Two." Uraxes looked to Myrikos for an explanation, but the Shield-Captain offered none. "You may think of this as an inadvertent test. One of your blood games. Your actions are perfectly within acceptable parameters."
"Who... are you?" Uraxes asked. The person, O5-2, merely tilted their head.
"A member of the Oh Five Council of the SCP Foundation. Come. There is much to learn."
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Idk why but I feel like the SCP Foundation would still persist into the 41st millennium. In fact, I have a small headcanon that Malcador and the Sigillites were the Foundation. Malcador may have even been a member of the O5 Council. Plus I've seen a lot of jokes scattered across the internet that the Shadowkeepers are basically the Foundation. So, this got made up ig.
Peace, love, and donuts: 8Ball3