Xavier was frogmarched into a dark room, handcuffed and with a rifle pointed at his back. As soon as he stepped in, the lights flickered on. There was a D-Class cuffed to a chair, swearing like a sailor.

"Eat shit, motherfuckers! Once I'm outta here, you'll be sorry!"

This wasn't much of a shock to the former doctor. He'd seen this many times before during his days working for the Foundation. Sometimes he was even in the observation window, taking notes and pressing warning buttons when needed.

But this was a special case, because this time he was the test subject. And Xavier could feel the eyes on him as he stepped closer to the shackled and incensed D-Class. He read the number on the prisoner's tag. D-8904, a serial killer infamous for his fiery temper.

Click.

To his utter horror, the murderer in question had been released from his restraints and was armed with a knife. D-8904 flashed a cruel smile, his eyes filled with homicidal intent. So, the doctor did what any normal person would do. He ran for the door.

Why does he have a knife? Did he somehow sneak it in? Or did they give it to him as part of the test?

Hold on. Are they trying to decommission me?!

Worse yet, Dr. Paris Kiran was present. Once Xavier saw her watching him, the color drained from his face and his claws returned.

Is that Kiran? Didn't they punish her for the 3017 debacle? Or any of her other ethics violations?!

Without a moment to consider what he was doing, Xavier began scratching at the door. But just as he was about to open it and run, D-8904 had him pinned against the wall.

The panicking humanoid let out a shriek when his wings came back. His feathers launched themselves at D-8904, ripping the man to shreds. Xavier was able to calm down shortly after.

While his natural weaponry retracted and he took deep breaths to calm himself, Paris and the other observers jotted down the events in their notepads. Security personnel handcuffed Xavier and escorted him back to his cell. Nothing else of note happened after that, but he was rather shaken from the ordeal.

The next day, he was outside of the facility with a helicopter whirring above. Then he heard a recording of Mr. Veers' voice.

"The staff there were going to hammer that 'non-binary' horsecrap out of her. Gender politics are a goddamn plague on our youth, one that deserves to be stamped out by any means necessary!"

"But of course she had to go crying to you! You've taken her from us without our consent and we want her back or else!"

Hearing those familiar and hated voices was enough to make him see red, thus activating his powers. Realizing that the sounds were coming from the helicopter, Xavier flew up to the vehicle and tore it to ribbons, including the radio playing audio recordings from the disastrous interview.

"Interesting. So SCP-8166 can use its wings to fly when needed," Dr. Kiran noted.

Thankfully, the anomaly in question was calmer. With his built-in tools gone, it was easier for him to be returned to his cell. But he was ordered to leave again an hour later.

"We want to see if you require your necklace to transform," Dr. Lachlan Vanderbilt explained.

Now he was becoming excited. "If I need it use my powers, could I be released without it?"

With a sigh, Lachlan replied, "I'm afraid not. You'd still technically be an anomaly in that case. That being said, you could be put under more lenient containment protocols if SCP-8166-B is needed for your metamorphosis."

"SCP-8166-B? You mean my amulet?" Xavier asked, to which Vanderbilt responded with a simple nod.

He was taken to a very small and cramped room. Once the door was bolted shut behind him, Xavier's breathing started to quicken. I really shouldn't have told them I was claustrophobic...

Dr. Vanderbilt watched with a remorseful expression as D-10639 entered, knife in hand. "Wassup, Foundation scum?"

"I'm not working for them anymore! Hell, they even contained me like they do with any other anomalies!"

"That don't mean shit to me. Anomaly or not, you'll always be one of 'em in my eyes. I can't kill the actual staff, but I'll do the next best thing by slitting your throat," D-10639 riposted. He then added with a spiteful grin, "And I plan to thoroughly enjoy it."

Xavier ran around the tiny room, hoping that the vengeful man wouldn't catch him. "Lockie! Kiran! Anyone! Help!"

Occasionally, D-10639 would catch up to Xavier, who would kick or punch him in the gut before running while his opponent was on the ground. Once he found a place where his pursuer couldn't reach him, he started looking for a weapon.

Unfortunately, D-10639 was able to climb up to his level and stabbed Xavier in the hip. The anomaly screamed in pain, collapsing to the ground. The D-Class grinned and sauntered towards his prey, holding his knife in the air.

Lachlan attempted to unlock the door, but was stopped by Paris. "Some advice: Don't help anomalies escape. That is, unless you wanna wake up in orange garb with a number in front."

"He's terrified and panicking! I cannot in good conscience allow him to suffer in such a way!"

"That's the point, dipshit. We're supposed to watch if he transforms even without SCP-8166-B. And we both know his emotions need to get out of control for that to happen, whether it's because of rage or panic," Paris snapped.

Lachlan sat down, a lone tear sliding down his face. "Firecracker...forgive me..."

To the shock of the murderous lab rat, his would-be victim had grabbed his wrist. He howled in agony when talons of tanzanite lacerated his arm. Blades of blue topaz pierced his abdomen, eliciting more pained screams.

Rubbing his eyes, he saw not a man, but a monster. Razor-sharp plumes launched themselves at his limbs, severing them from his body. What little remained of D-10639 was pinned to the ceiling as Xavier beheaded him with his left hand.

Some of his feathers anchored him to the ground as Xavier lowered himself, exhausted. In the observation window, Lachlan wrote down what had happened. To his right, Paris began modifying the SCiPNET file for SCP-8166.

"This is a rather...intriguing development, I must say," Thomas said after he read over the report Paris gave him.

"How will SCP-8166's containment procedures change, in light of this new information?" Paris asked.

"We will continue to coat the doors and walls with the tungsten-coated chromium, cobalt and nickel alloy already in use. However, given that SCP-8166 can fly with its wings, the ceiling will need to be protected with the same materials as well."

"I would like to propose we begin testing the object's natural weaponry, such as their durability and the limits to what they can pierce through."

Thomas was quiet for a bit, then said, "I will consider your suggestion."

Of course, it didn't take long for him to make up his mind. SCP-8166 is one of the most fascinating anomalies in containment. Further testing should help us understand its properties better.

Sure, he may have been my friend once, but remaining "friends" with 8166 would compromise my position. Xavier Dusk is now too much of a liability for me to keep in touch with him. He was a brilliant young man, and was quite useful in my schemes. But now that I have Kiran and Edwards, I can safely discard him.

Paris woke up to a phone call, which she answered upon seeing who was calling. "Yes, sir?"

"I have excellent news. You may begin testing on SCP-8166."

"Marvelous! What will the procedures be?" Paris asked with a wicked grin.

"I will discuss that with you in my office, Dr. Kiran."