((A year older and a year wiser.))
Golden eyes narrowed. Rainbow Dash stared into them. She wondered how it was possible for something in such warm colors to convey such coldness. They were colored like fire, but Rainbow felt frost sting her cheeks just by looking at them.
Captain Spitfire spoke in a slow, dangerous tone. “Private Dash, what are you doing?”
Private Dash. Sometimes she forgot she had a rank now. The Wonderbolts were separate from the standard rank order of the Guard. They were a tightly-knit outfit, and they never referred to one another by rank except for calling Spitfire 'Captain.' The fact that Spitfire was addressing her as 'Private Dash' was a screaming alarm that things were about to go very sour, very quickly.
Not that Rainbow didn't already know that. She straightened her posture, holding her wings out to bar access to the door behind her. “I am protecting the Princess, ma'am.”
Spitfire's mane rustled as the breeze momentarily shifted direction. Her nostrils widened as she leveled a thin-lipped stare at Rainbow. “I have permission to enter, Private.” A snarl accompanied her re-iteration of Dash's rank.
Rainbow kept her stance steady, and her eyes locked with those cold golden orbs. Sheer force of will kept her knees from trembling. “Beg your pardon, ma'am, but no you don't.”
The Captain stepped forward, her face hovering inches from Rainbow's. “Private Rainbow Dash, you will stand down!” she barked.
Rainbow didn't flinch. She couldn't let herself flinch. If she flinched, even for a moment, she would start to doubt herself. Once she let that seed of doubt take hold, it was all over. The thing in front of her would seize upon it and exploit it, twist everything around until she would believe anything that came out of its mouth. She had let it happen to her before, she couldn't let it happen again.
Rainbow Dash spoke through gritted teeth. “All due respect, but you are not my captain.”
The golden eyes flickered for a moment, and then Spitfire's expression softened a bit. “This is about that thing, isn't it? Rainbow, you can't let that one incident run the rest of your life. You are stronger than that.”
“One incident?” Rainbow repeated, a harsh scoff bursting from her. “One year. That thing played me and my friends off of one another for a whole year. We still haven't put together which times we actually shared with each other, and which times were just it feeding on us.”
“And then you caught it,” Spitfire said, flicking her wings impatiently. “It got sloppy, and you and your friends sniffed it out. Now it's stuffed in a jail cell. Story over. This is not the sequel, Private Dash. You can't just go seeing changelings everywhere.”
Rainbow Dash set her jaw. “You are not Captain Spitfire.”
“I am Captain Spitfire!” she bellowed, stomping a yellow hoof on the flagstones. “And I don't have to prove it to you! I can have a squadron of Royal Guard haul you straight to the court-marshal you'll be facing for insubordination if you don't stand down!”
Rainbow Dash took a deep breath. One year ago, she would have let this thing play her for a fool. She had let a thing just like this one play her and all her friends for fools. It hadn't even needed to try very hard. Each of them had so wanted to believe the other just wanted to spend time with them that Rainbow never even questioned that Applejack had said she was too busy to come to the lake but then showed up anyway. Pinkie had never even bothered to ask why Dash was out playing pranks with her during her usual naptime. Fluttershy had never spoken up when Twilight showed up at her cottage, even though she was supposed to be in Canterlot.
Foolishness was the price of wisdom. Dash had paid a year of being a fool, and now she was that much wiser. She had learned her lesson, and she did not intend to have to learn this lesson a second time.
Rainbow Dash took a step forward, pawing her forehoof at the ground. “You just made your mistake, changeling.” Her eyes glinted in the light. “Spitfire wouldn't need a squadron of Royal Guard to take me in. If you were really her, you wouldn't be afraid to take me on by yourself.” She crouched into a battle-ready position, her wings cocked and ready to give chase if the thing tried to flee.
“Private Dash, I'm only going to give you one more chance—”
Private Dash charged.