A Hollow in Rainbow Sand

Location: Luna and Nyx's Chambers, Canterlot Castle/PoV: Jack

So it's been a few days since we helped Nyx to relieve her stress. Since then, Celestia has had the guards discreetly spread rumors that Nyx was the product of a magical accident caused by bad timing and a few misplaced runes while testing a new spell. The people bought it, surprisingly enough, and accepted her very quickly.

Speaking of Nyx and Luna, at the moment we were in the middle of a game of "Sorry!" that I pulled from a random earth. Celestia would have joined in, but there were more Nobles than usual in Day Court today so she was having to work on paperwork.

"Hah! I've got you this time!" Luna said as she played a card that let her swap one of her pieces with Nyx's.

"Oh well. The humped-backed claw bugs are telling me something." Nyx said with a hand to her ear.

"Oh shit! Last time they showed up was before that rather memorable night at the gala!" I exclaimed as I tuned into that dimensional frequency.

"PiNk priSm..." The beings, which were actually sentient void beasts, began softly. Suddenly, a pressure that I heard more than felt appeared.

"DANGER!" The sudden, almost demonically deep tone that this word was delivered in knocked both me and Nyx flat on our asses!

With that, the pressure faded and the frequency was silent. Nyx and I looked at each other in confusion, while Luna fretted over us due to our falls.

"Pink prism, danger? Now what could that..." I trailed off as I remembered the magic almost similar to my own which belonged to a certain pink party pony, "SHIT! We need to get to Ponyville, NOW!"

With those words I immediately warped to the outside of Sugar Cube Corner. Seeing the ponies fleeing the building made my bad feeling worse as I worked my way through the crowd.

Once I was inside however, I was hit with one of the most insane aura's I'd ever felt. Madness almost literally dripped from the walls and ceiling. I rushed upstairs and broke down one of the doors to see an eldritch abomination hovering over a cowering Pinkie Pie.

"HEY, BARNACLE BEARD!" I exclaimed as I summoned a rock and threw it at the back of this...thing's head. The stone bounced off harmlessly, but it got its attention.

I flared my full aura at the thing, then focused that aura into my throat. I didn't know if this would work, but apparently if you use this with a bit of kaleidoscope magic...

"BEGONE" The word was an order, a command to the world, no to the universe. It was an order to use everything it had, even the darkest of magics to banish this foul existence which did not belong!

The power flowed through me, and if I hadn't trained to disperse any recoil from using too much power throughout my entire body, then I likely would have died for a third time. As it was, I knew my throat was going to be absolutely killing me later.

There was flash of rainbow light that blinded me, and when I could see again the creature was gone. I ran a quick scan through the kaleidoscope and confirmed that it wasn't anywhere near this dimension. With that done, I staggered over to Pinkie and put a hand on her shoulder.

"Pinkie..." I said, my voice extremely hoarse from the force of using that much power, "Pinkie it's okay. That thing is gone now."

She opened one of her eyes, peering cautiously into the world around her.

"Jack? Is...Is that you?" She asked in an absolutely terrified tone, which broke my heart due to how such a happy pony could be reduced to this.

"Yeah it's me. What happened?"

"W-well, I was just looking around to see what I would see today in the place only I can see...I wound up looking at that thing and it noticed. I pulled away, but it followed me and...and..."

She broke down into tears as I pulled her into a hug. It was starting to come together for me now. Pinkie wasn't using a variant, she had the real deal. The kaleidoscope had chosen yet another wielder.

It's been a week since then, but it took a few days for pinkie to get back to her old self. She was lucky that she pulled everything of herself into her mind when that thing appeared or she might have gone insane. After she had recovered, however, I went to talk to her about training her magic.

The first thing I taught her was how to sense the general aura of worlds like the one that thing was from. that way she would know to instinctively avoid them. But when I tried teaching her how to summon objects, I found that she already had a grasp on that and teleporting. All I really had to teach her was how to sync up with alternates and how to find specific worlds, which was a rather pleasant surprise.

She also helped me with using the dimensional refraction phenomenon. Though the way she did it was rather unorthodox.

Flashback: Two Days Ago/Location: A random uninhabited desert planet

So here I am, working with the kaleidoscope to practice firing dimensional beams. Pinkie suggested that if she practiced enough then she might be able to create small ones that simply let her use the kaleidoscope from a distance. I tried to tell her that she could simply do without the beam, but she said she wanted to prank Twilight with the possibility of an earth pony having unicorn magic and I just couldn't pass that up.

I checked the time on Equus, and saw it was getting late. Just as I was about to Pinkie to call it for the day, she went and shot multiple beams at one spot!

"Holy shit Pinkie! How'd you do that?!" I asked in awe.

"I made multiple 'me's in a sub-dimension who all charged up the beam, then opened the door to the sub-dimension facing the way I wanted the beams to go!" She exclaimed with a finger pointing up and her head tilted to the side as she smile with closed eyes.

'Cute...' I thought before shaking my head and focusing on what she said, trying to decipher just what she meant.

'Okay, so it sounds like she made a pocket dimension where the duplication of an object or person is possible...Then had them all act in sync before opening multiple portals. I wonder if... I trailed off as I created a pocket dimension for myself and then focused on creating reverse-mirror images of myself so that we all faced the same way. As one, we raised our hands to our mouths and bit our thumbs to draw blood which we smeared on our palms. Then we stretched our hands out in front of us.

"Gran Rey Cero...Barrage." We intoned before I opened several portals in front of the mirrors which the massive attack came through. It hit a dune that was as tall as mount Everest in the distance and caused an explosion which I had to shield Pinkie from the shockwaves of. When I looked back, there was a massive crater where the dune used to be.

End Flashback

I told Ulquiorra and the princesses about my new attack. The princesses nodded and accepted it until Ulq did something that was seriously out of character for her.

She paled and passed out! I made sure to take blackmail pictures but the fact that this attack had this effect on Ulquiorra of all people told the princesses just how bad this could be. I promised not to use it on Equus and if an opponent ever warranted it I would take them off world. Though that was a no-brainer considering if it took that much firepower to destroy then odds are it had probably not come from this world.