Trixie

As I walked through the forest, scanning the ground for herbs, my mind wandered to my acquaintances in Ponyville.
I'd traveled there a few times over the past week, mainly herb gathering - it surprised me often how many different herbs Zecora needed and the quantities she needed of said herbs - and I'd noticed something... off about the Ponyvillians. They hardly even knew who I was, despite the fact that I'd mistreated them so much during the whole Alicorn Amulet snafu.
Having collected the needed herbs, I concentrated, thinking of the cottage I now called my home; a bit off-putting at first, but I'd grown to appreciate its subtle, tribal beauty.
A flash of light, a burst of sound, and I was standing on the doorstep. I took a moment to gather my bearings and stepped inside.
"I'm back with the herbs, Zecora." I said, placing the ingredients next to her cauldron, which was bubbling and frothing with some potion or other.
Then again, when isn't she making some crazy elixir or cure-all? She hasn't stopped making stuff since I started helping her.
Zecora grunted, holding two bottles in each hand and one in her teeth. Setting the bottles down, she started adding their contents into the cauldron, slowly stirring the brew.
"Do you need any more help?" I asked, secretly hoping not. To my relief, Zecora shook her head, and I left her to her concoction and went to the meditating pool.
It's strange; the more you get to know Zecora the less she talks. It's understandable, I guess; coming up with rhyming couplets on the spot 24/7 must get hard after a while...
I concentrated, and stepped out onto the water, magic keeping me from sinking into the pool. I sat down cross-legged on the center of the pool and cleared my mind. I levitated a ball of water in front of me, focusing intensely. As I concentrated, the ball of water split into two smaller balls, elongating into streams of water, which then started swirling around in a strange aerial dance. I focused more, and levitated a second ball of water, the two streams circling around it eclectically. I levitated a third orb, and had the two orbs orbit each other while the streams continued their strange dance.
I stood up then. The water dropped slightly, but I refocused and continued the exercise, moving the water around me in circles, increasing the speed ever so subtly. After a couple of minutes, the water was whipping past me in blurs as I concentrated.
Now for the hard part...
I shut my eyes, and turned the water to ice.
As I opened my eyes, I was greeted by a frozen orb levitating inches from my face.
I did it! I actually did it!
I checked off another item on my mental checklist of the spells I'd been able to perform while my magic had been boosted by the amulet. So far I'd been able to create pies, levitate a fruit cart, create a chariot, make a pony dance (with consent, of course), and now, freeze things.
Next up is age spells, and then whatever I did to Pinkie Pie.
In my exultation, I'd let my concentration slip and fallen into the pool. Climbing out, I used a spell to dry myself off and resumed my normal meditation.

Later That Day

As I strode into town, something struck me as off about the usually bustling village.
All was quiet. Not a footstep echoed through the streets but mine, not a voice could be heard. A lone tumbleweed made its way across the street unhindered; all the usual abandoned-town cliches.
I walked up to a stand run by a woman named Daisy, one of the few vendors who carried the exotic herbs that Zecora's recipes called for.
I rang the small bell and thought back to yesterday as I waited for Daisy to appear...

"Why hello, Daisy. How are you today?" I'd asked, giving her a radiant smile. I'd always tried to be extra nice to the people I'd hurt directly while using the Alicorn Amulet; I'd forced Daisy to hang up flags of me all over Trixieville.
"Why hello there, uh..."
Daisy's voice had trailed off as she stared at me blankly.
"Who are you?"
"Why, don't you remember me?" I'd asked, giving her a confused look. "It's me, Trixie. I come here every week to pick up herbs for Zecora, remember?"
She'd nodded then, and a look of understanding came into her eyes.
"Ah, Trixie! Sorry, there's been a lot on my plate lately; surely you understand."
"Of course I do. At any rate, I'm here for some Poison Joke Powder."
"Let me see if I've got any..."
Daisy'd darted into the back room, knocking over a bottle of herbs on her way. She quickly caught it and placed it back on the shelf. As she entered the back room, I examined the label:

Poison Joke Powder

"What's going on around here?" I'd said to myself.
Muffled voices started emanating from the back room, and, curious, I'd enhanced my hearing via magic to see what the voices were saying.
"Look, I have no idea who this Trixie chick is, but if you don't get rid of her soon, we'll-"
"She said she knows Zecora! We're spread thin as it is; we can't afford to lose anyone else or we'll never hold up against an organized-"
"Okay, okay! Just... Make her go away. We can't deal with any variables right now!"
"How!?"
"Just give her the herbs she needs and she'll leave!"
"How am I supposed to know anything about herbs? Why was I stationed here? The only 'herbs' I've ever seen are brambles and the occasional tumbleweed!"
"Then tell her you're all out! Just do something!"
Daisy'd exited the back room, a nervous look on her face.
"Sorry, but we're all out of Poison Joke Powder. Come back some other time. We get new stocks tomorrow, and-"
She'd stopped then and winced, as if she'd said something she wasn't supposed to have said.
"I'll come back another day." I'd said, ambling off. "Have a nice day, Daisy!"

My thoughts were interrupted by the sound of a door opening. I looked up to see Daisy walking towards the counter, a nervous look on her face. She smiled weakly at me.
"Hello again, Trixie..."
"Hello, Daisy? How are things?"
"Oh, you know..."
I looked around, puzzled.
"Late again."
"Who's late?"
"My friend Raincloud's late. We always hang around here and chat until I have to go back to Zecora's. It's a shame; I'd found out something really interesting."
"She must be sick or something. Listen, our supplies have been delayed for a few days, so if you could come back, say, Saturday, that'd be-"
Her words were cut off as I leapt over the counter, tackling her and covering her mouth so she couldn't scream for help.
With my other hand, I grabbed her necklace.
"Wouldn't want you signaling your friends, now would we?" I said. "Tell me; Where's the real Daisy?"
She tried to say something, but with my hand over her mouth it was muffled, so what she said came out as "MMM MMM MMM MMM MMM-MMM!"
"You are most definitely not the real Daisy." I said, glaring at the impostor. "People who don't exist can't very well get sick, can they?"
The fake Daisy's eyes grew wide, and I nodded.
"That's right. There is no Raincloud. Now what are you and what have you done with Daisy?"
The impostor bit the inside of my hand, but I held on despite the pain. I closed my eyes, concentrating...
We appeared back at Zecora's hut.
Zecora looked up from her potion, eyes wide in shock.
"Trixie, what on earth is going on? Who's this person you've landed upon?"
"I knew something was off when I visited Ponyville yesterday, and now I have proof: the people in town are not as they appear!"
I concentrated again, and my necklace started glowing.
"This spell should get rid of any illusions or shape-changing magic." I said, releasing the spell and watching light blue sparks cover the fake Daisy. When the sparks lifted, Zecora and I both gasped.
"Dark tidings you bring: You've found a changeling!"