Hivemind Control

Shining Armor did not dare draw his shortsword. As big as the cell was, it was still very small. It was made to hold a maximum capacity of two, and there were currently three ponies in there. It was cramped enough with that many bodies that every swing would need a fine amount of control not to hit Luna.

Luckily, he didn't need to fight that hard. If he stalled for long enough, the guard would come back with the keys, and probably reinforcements. They would see two of him and immediately his claim that the other was a changeling would be called into question. Of course, that would mean he would be subject to investigation, as well, but that was okay. Luna would be safer, and that was what mattered.

"Cosmo" threw the first punch. While Shining was able to duck out of the way and avoid the blow, he immediately felt his back against the wall. There was no room to maneuver. When the next blow came, there was no dodging, and he had to block it. As he deflected his own hoof, he could feel every crack and crevice in the changeling flesh. It was astounding to him that Luna hadn't felt it. It was hard and scratchy, and had scraped off a bit of his epidermis with the impact.

It was time to go on the offensive. Backed against the wall, he had no room, but if he swung a few hooves, he would either knock this changeling out or cause him to back up a few steps. Either case was good for him. He focused on low swings. They may have been easier blocks, but the only way to dodge them was backward, and after a few swipes at the air, Shining had taken two steps forward.

He suddenly switched up his maneuver and threw a quick jab, smashing his hoof right into the changeling's nose, earning him a third step forward as his foe stumbled back. It was a critical blow in Shining's favour.

He jabbed again, but this time was not so lucky, as a simple duck to the side was enough to avoid the blow. Before he could retract, Shining was hit by a rogue swing colliding with his ribcage. The off-center blow was something he was not prepared for, and forced him to stumble to the left and recenter himself.

He had more forward and backward maneuverability in this position. The cell was deeper than it was wide, but he considered his new position to be just as narrow. His current stance put him between the changeling and Luna, and that was a good position to be in. He just had to hold his ground.

That proved fairly easy, as he could stay on the offensive, throwing his hooves and then pulling back into a guard position. He would not allow the changeling to sidestep him this time. He was unwilling to dodge, though, as he would not give any ground. He had to block or redirect any blows.

As the changeling swung a particularly wide hook, Shining grabbed him by the wrist and pulled him to the ground. Not wanting to miss this advantage, Shining followed him down, rolling him onto his chest and pinning his arms behind his back. Shining could feel the fluttering of the invisible wings against his thighs as the changeling struggled to break his grip.

"I knew from the moment we met that you were trouble," huffed Shining. "What say we make this easy and you return to normal?"

"What say I don't?" grunted Cercus, struggling just enough to ensure that Shining had to focus on him. "I don't give up so easy as that."

"Give up?" grunted Shining. "Just admit that you lost. You'll be found out soon enough, just make it faster and less strenuous on your part, and you won't suffer as long."

"I haven't lost yet..."

As Shining cocked his head to the side, he felt a sharp sting in his back. He turned, and standing behind him was Luna, a small, curved knife in her right hoof and a clear bottle of thick, green liquid in her left. A bit of green and red fluid dripped from the blade. Just where his halfplate gave way to flesh, there was a trickle of blood.

Immediately, Shining began to grow faint. After a few seconds, as the world around him began to spin, Cercus wrenched a leg free and managed to toss Shining to the ground and pin him down just as Luna wiped the knife clean and hid the bottle. "Did I do good?" she asked.

"Very good, my pet. Now keep quiet."

As the guard came back with a key, Shining found that he could not move. He was tied up, but more than that, he couldn't speak. When the door opened and seven guards came in, he couldn't say anything to defend himself. A muscle paralyzer had stopped his voluntary movement. He felt sluggish, and for a moment, he wondered if his heart would fail, but if it did, there was nothing he could do to stop it.

"This is a changeling," informed Cercus. "He was impersonating Luna's stallion companion, and after I caught him, he turned into me to fool you."

"How do we know it's not you that's impersonating him?" asked one of the guards. "What if you're the one trying to fool us?"

Shining felt a burst of pride. He had known that the guards would take them both in for investigation, and only he, being an actual unicorn, would pass scrutiny. A letter to Cadance telling her to come and decide would even be able to yield immediate results. However, his mood changed to immediate dread.

"I saw the transformations," said Luna. "The one on the ground is the changeling, and Shining Armor was very brave in tying him down."

With that, his fate was sealed. Having Princess Luna as an eyewitness could, and likely would, put a stop to the investigation. He desperately hoped that somepony, anypony, would run the tests and find out the truth, but as he was carried up the stairs and loaded into a carriage with the changeling impersonating him, he could feel that the carriage driver was also a changeling. He was being carted off to who knows where, by creatures that intended to devour him.

"I hope you're comfortable," smiled Cercus, kicking him in the gut. "I told you that I hadn't lost yet. I had plenty of room left. Sure, I'll have to keep away from Luna for a few days while you're in transition, but it'll all be worth it when you're serving me breakfast."