We finally reached Ponyville. The ponies were offering food to us every few minutes, probably thinking that ponies would buy their food if royalty bought them. I declined every single time but Pinkie managed to clear the whole trolley and somehow paid for all of it. I could only tell how much the ponies wanted Pinkie Pie to go on the train again.

Twilight let out a deep breath as we all stepped out into the sunlight, "Ok everypony. I think that we deserve a rest. Let's meet at my castle in around an hour. Is that alright with everypony?" We all nodded one another but going to our separate paths. I flipped my wings and went into my castle. Moondancer was going to have to find a way up it seemed like, but there were stairs that led up to my castle from the ground.

Apple Watch greeted me, "Howdy Princess Rainbow. Glad to see you back."

I rolled my eyes, "Rainbow. It's nice to see you again, Apple Watch. Where are Spirit Runner and Fire Bright?"

Apple Watch chuckled, "Ain't glad to see me, are ya, Pr-Rainbow? Spirit and Fire are patrolling. Ah can call 'em over if ya want me to."

I nodded, "Yes, do it." Watch ran out of my sight before coming back with the others after a couple of minutes. They all bowed again, with small smiles on their lips.

I rolled my eyes again, "You guys do know that you don't need to do that, right?"

Spirit smiled, "We know Princess Rainbow, but Princess Celestia prefers to have guards, even personal ones like us, to not have a bond with the princesses. This would be for safety purposes."

I declared, "Too bad because if your backs are at risks, I'm saving you guys too."

"No Princess," Fire said, "We can't have that. There's a reason that we are the guards."

I replied, "And there's a reason why I'm the Element of Loyalty. I would never let you guys hanging, even if you are supposed to protect me."

"You can't save everypony and you know that."

"But the least I could do is try." I levitated the doors open, "C'mon, let's go and hang around in the castle."

Fire shook her head, "Princess, I'm afraid that we have our duties. There is extra security due to the invasion and as the commanders of your armies, we need to keep all of them in order." I sighed and flew in by myself. The Dark Wings were hopefully ready to hang out with me.

After a couple minutes of flying around, I found Dragon Tail outside, shouting, "Ok everypony! That's enough practice. Let's head in and-"

Dragon stopped as he saw me and immediately bowed, "Princess Rainbow Dash!"

I sighed, "Just Rainbow."

He nodded, "Just Rainbow. Do you need something?"

"Nope. I just came for a fly."

"Oh, we were hoping on starting some sort of routine for the upcoming war."

I bit my lip, "I'm sure that Twilight can handle the things with the Elements."

"Then did you form the Dark Wings?"

"To become the best flyers, to out maneuver the Wonderbolts, and to be a super mega battle pegasi."

"You're the captain. Make a routine. Practice."

I nodded, "Ok, Dragon. I'll check what each pony's speciality in flying is and create something. Keep up the training. I'll check on you after I-" A letter popped in front of me and I caught it with my hoof.

I opened it and read in my head:
Rainbow,
This is Twilight. I'm sorry for contacting you like this but this is urgent. Starlight is missing and Trixie is also missing. Her wagon is still here. Sunburst says that he'll tell us where he lost saw them when you and the other girls come. We're in the castle library. Be prompt.

From,
Twilight Sparkle

I looked up from the letter and sighed, looking at the team, "Sorry, Starlight is missing. I've got to go help find her. Dragon, you're in charge until I'm back. Keep going with the exercises. If I don't come back before dark, then you're going to have to finish the practice at a suitable time."

Dragon sighed, "Ok Cap. Back to training everypony!" I flew out of the palace swiftly and crashed into Twilight's library from her window.

Twilight barely looked up from the book, "Hi Rainbow."

I chuckled nervously, "Sorry Twi. I'll try to fix it." I stared at the shattered pieces and concentrated on making it a window again. The pieces floated up and sorted with each other and I levitated it to where the window was prior. I released it there and the window shattered again.

Twilight said, ignoring my failure with fixing her window, "As you all know, Starlight is missing. Sunburst?"

Sunburst said, "Trixie wanted to show Starlight some new move and they sent me to the antique shop so they could plan it out. After all, Starlight is the magic assistant in her show so I thought that it was only fair for me to give them time to set it up. After an hour or so, I decided to check on them and they weren't there. I checked everywhere. The town. The library. Everything!"

Pinkie Pie smiled, "Ooh! Hide and seek! I love hide and seek." She looked around, lifting the pots and the chairs, looking for Starlight as if anypony besides her could fit in there.

Pinkie put a hoof under her chin, "Ooh. She's good." Suddenly, Pinkie's body shook as if there was an earthquake.

Twilight gulped, "Was that a doozy?"

"Yep! That sure was a doozy," Pinkie cheerfully answered as her body shook again.

I asked, "Where is it going to happen?"

"Underground!" I groaned and folded my wings. Underground was a Pegasus’s nightmare. Most Pegasi are claustrophobic due to the fact that they weren’t free to fly or anything in a tight space.

Fluttershy said, “Un-Un-Un-Underground?”

Pinkie smiled and said in a sing song voice, “Yessire!”

Twilight asked, “Where underground?”

Applejack sighed, “Those gosh darn Diamond Dogs must’ve taken her.”

“But the Diamond Dogs don’t even know who Starlight is! It would be plausible if it was Rarity since she did annoy the dogs or one of us.”

I said, “Let’s ask Trixie. She saw Starlight last.”

Sunburst shook his head, “I haven’t seen Trixie either. Believe me, she would be here if I have seen her at all.”

Twilight decided, “The Diamond Dogs are the only creatures that live underground that has a grudge on ponies. Let’s check them out and see if they are keeping our friends hostage?”

I blinked, “Since when have we become friends with Trixie?” Twilight gave me a look before shaking her head and trotting out of the room, the rest of us following. We eventually reached the place where Rarity had been caught by the dogs a really really long time ago.

Spike shouted through one of the hole saw on the ground, “Hello?!” My wings flared up as I heard digging sounds, ready to attack if needed.

A dog growled from the hole, “What are pony and dragon doing here? No stealing gems...”

Twilight cleared her throat, “I am Princess Twilight Sparkle and I have reason to believe that you are holding my friends hostage in there. As the Princess of Friendship, I demand that you let us underground safely and lead us to them.”

“No hold pony in prison,” the dog growled back, “And pony no have control over us.”

“I will do anything to find my friends,” the princess warned, “This includes forcefully going down there. I suggest that you let us in with peace.”

Rarity batted her eyelashes, “I hope you remember the last time I was in there? I was alone, a damsel in distress, but I made it out. It would be absolutely lovely to see the place again and for return for checking out your caves... I’ll help you mark around two wagon full of gems.”

The dog hesitated and nodded, “We agree with terms. Follow me.”

As they headed down, Fluttershy whispered to Rarity, “If you want, I’ll keep you company in these caves after we search it thoroughly.”

Rarity shook her head, “Darling, your animals need you. Sassy can help run my shops while I’m not there. Besides, I can do the job alone.” I saw Twilight beam at her as we continued down the tunnels. The smell of the air became worse and worse as we traveled deeper. The dog finally stopped in front of prison cells,

“Satisfied?”

Twilight casted a spell and sighed, “No sign of life in these tunnels. I guess that the dogs weren’t the ones that had captured Starlight and Trixie.”

I groaned, "Can we get out of here? All these tunnels are making the air stuffy."

Twilight shook her head, "No. If there is an unicorn here, there could hide Starlight and Trixie easily."

"Which unicorn would want to hide ponies here?"

Pinkie squealed, "Ooh! Guessing game! Hmm... Is it-"

I interrupted, "Pinkie, we're on an important mission right now. No time for guessing games."

"Awww..."

Twilight sighed, "You're right Rainbow. They aren't in these tunnels. We should go back to Ponyville and look for clues." The five of us went back to Ponyville as Rarity stayed to find gems for the Diamond Dogs.

When we finally got back to the throne room, we sat on our respectful chairs. Before anypony could say a word, there was a giant flash and Trixie appeared in front of us.

Trixie panted, "Trixie and Starlight needs help. It is all Trixie's fault."

Twilight asked, "What happened, Trixie?"

Trixie looked down, "Trixie worked for the enemy, the Rebellion. Trixie brought Starlight there. Leader wants to recruit Starlight and will kill Trixie and Starlight if Starlight doesn't agree."

Twilight blinked, "Can you lead us there?"

"Trixie can." We huddled together and there was a giant flash of light as we got there. It was dark. I lit up my horn to see a plain cave. I shuddered. I hated caves. Meanwhile, Fluttershy was shivering, feeling the effects also. I lifted her up and wrapped my wing around her.

Just in time to hear Starlight say one word, "Yes."

A maniac laugh rose up from inside the cave, "Welcome Starlight, to the Rebellion."

"What do I need to do?"

"I want you to spy for us. You are the student of friendship after all. Spying on the princesses and their friends should be rather easy."

"Sounds good."

"Gather any information that can be useful. Go out and teleport with Trixie to the main land. I must speak to the highest position ponies in here, the ones who have stayed for a decade." Trixie quickly teleported the five of us back to the land as she disappeared, presumably to teleport Starlight here. They appeared a few minutes after.

Starlight said, "Sorry I was gone. I had to check something really quickly. Sunburst showed me a spell."

I raised my eyebrow, "Really? Can I see it?"

"Since when were you interested in magic?"

Sunburst interrupted from a corner of the room where he was waiting for the girls to return, "Since I wasn't with you, it would be highly strange for me to show any such spell to you, Starlight. We were actually searching for you."

Starlight hesitated, "Searching... For me? Did something happen?"

I pushed my nose to hers, my eyes threatening, "You bet that something happened!"

Twilight levitated back me back to my sit, hissing into my ear so only I could hear, "Undercover, Rainbow Dash."

The purple alicorn grinned at her pupil, "Starlight, what Rainbow means is that we went through some trouble trying to find you. We thought that the Diamond Dogs had taken you since I know that you go there with Trixie from time to time. Don't worry about it. Why don't you take the day off with Sunburst and Trixie?"

Starlight hesitated, "You sure, Twilight?"

"I'm sure," she replied, "Besides, Sunburst doesn't visit that often so you two should enjoy your time together. Rainbow and I have some princess duties and the others have already volunteered to help out."

Applejack raised an eyebrow, "We did?"

"Of course you did. Did you just forget about it?"

As AJ opened her mouth to tell the truth, I said, "Oh yeah! Right. I totally forgot that I have a meeting with my... uhh... royal cooks! I need to borrow Pinkie and AJ. That all right with you, Twi?"

Twilight nodded, her gratitude showing through her eyes, "Yes, that would be splendid."

Starlight sighed and went out the door, "Thanks Twilight! I'm going to go now." Sunburst and Starlight both went out the door, chatting to one another like old buddies.

I gave a sigh of relief, "Whew. That was close. I think that Starlight knows that something is up."

Twilight nodded, deciding to take charge, "Rarity, Pinkie, and I are going to investigate using Trixie's teleportation machine. I will study it tonight and see if I can make a copy and see what I can do. It should be quite easy. After that, I will offer a hoof of friendship to whichever pony it is. Hopefully, they will realize their mistake and decide to become friends with us. It's the perfect solution! Oh and your job, Rainbow, is to distract her with Applejack. I assume that you have Princess things tomorrow?"

I chuckled nervously, "Uhhh... Moondancer probably made the list already. I kind of left her in charge of my events and whatnot. Eh, she'll be fine. Besides, it's not the end of the world if I don't show up. I'll just ask to send an apology letter with some sort of excuse."

The princess sighed, "I suppose we're lucky for Moondancer then. Let the plan... begin."