I lose track of where Luna is taking us, and nearly get left behind a few times. We have to walk through the hidden maze of Canterlot Castle for about half an hour, and I am exhausted by the time we stop outside a heavy wooden door. A plaque hangs on the wall, written in Old Ponish. I can just about understand what it says.

Private - No Entry Without Permission From Princess Luna.

The door swings open and Wishbone, Luna and I walk through. There are three beds - two single beds and a double bed, presumably for Princess Luna - but there is no sign of bedding on any of them. There are a few cupboards in the room. Luna opens one with her magic and out falls said bedding. It glides over to the beds and each pile makes itself into something I would actually want to sleep on.

Sleepily, I ask Luna, "Which bed do I get?"

"Either one of the singles. Just to let you know, you will have to stay here for a few days. You might be able to go down to the Lunar Guard Barracks during the nights when you're awake, just to socialise."

I choose the single bed on the left of the room and snuggle under the covers. The smell of lavender drifts my way as Luna casts a spell, and I fall into slumber.

I find myself in a castle made of brilliant blue crystal. A light grey stallion with an almost black mane is stood on a balcony a few metres away from me. He wears a blue cape with a white fur trim, and a golden crown. He looks familiar somehow.

He turns and his blue eyes look sadly at me. He says, "Moonlight, we meet again." Sombra.

"Do you think that I want to be involved in your lunatic schemes?!" I snarl at him to hide the fact that I am terrified. The fact that he is actually Dreamwalking and not a figment of my imagination just makes me fear him even more.

"Oh, I clearly frightened you earlier. The problem is, I never really introduced myself. Well, this is how I used to look before I discovered dark magic."

"Why do you think I care?'

"You do care, or you will in time. I tried to learn all I could about magic, but it turned me into a monster." His appearance changes: his cape turns from blue to blood red, and his eyes change to that same hue. Black armour forms around his neck and hooves, and the crown turns grey with red crystals embedded in the metal. The whites of his eyes shift to a sickly acid green and give off purple smoke.

I hear Wishbone and Princess Luna approach from behind, but don't turn to face them. "So you are a monster. What else?"

"Do you think that I like being this way? At first, the power went to my head, and I ruled with an iron hoof until Princess Celestia and Princess Luna banished me. Now that I am back... I wish for that to change, but I am unable to get into the Crystal Empire because it is protected. I would love to ask someone if it is possible to reverse this," he gestured to himself with a front hoof, "but just imagine me walking into Canterlot Castle and asking to speak to Princess Celestia."

"It wouldn't work, would it." I can see his point of view now. "Oh. I have no idea if this dark magic can be reversed, but maybe somepony as powerful as the Princesses can do something." I turn around to face Luna and Wishbone, who are both glaring at Sombra. "Right? Could he be helped?"

The scene changes, and Sombra disappears. From the balcony I watch ponies, chained together in lines, descend into a mine.

"This is what he did before Celestia and I intervened," Luna spits, wrinkling her nose. "He knows ways of taking a pony's free will away with his dark magic. He will not change, which is why I am here to protect you."

"What if he doesn't appear in my dreams again after this?" I see Sombra, in his pure, uncorrupted form, out of the corner of my eye. He raises an eyebrow.

"Then Wishbone Willow and I will not trouble you further, and allow you to get a decent night's sleep."

Sombra winks and disappears. Princess Luna may refuse to help him, but means that somepony has to, and that pony will be me.

I wake up and crawl out of bed. My short grey and purple mane doesn't look too bad, so I decide to leave it until after breakfast with the Lunar Guards. I wonder briefly if the Barracks will look any different to when I was last there, over a thousand years ago.

"Moonlight," whispers Wishbone.

"Huh?" I ask sleepily.

"Don't talk to King Sombra any more. He's trying to manipulate you."

"Ok. I won't speak to him any more." If he speaks to me, that's fair game, isn't it?

When we're all awake and don't look like we've just crawled out of bed, Luna leads us back through the maze of passages and hallways to the hidden tapestry. When we walk through, she teleports us just outside the Lunar Guard Barracks, and they look just as they did all of those years ago. Same dark colour scheme that doesn't match the castle, same banners hung up on the walls, same flags flying above it.

The sun is setting now, and Celestia waves at us from one of the balconies. We wave back and Luna raises the moon. Its light brings out all of the softer shades and hues that I love.

Luna asks us to follow her into the Barracks. I hear bat ponies talking to one another, and then they all fall silent save one, who sounds like a stallion. He addresses the other bats and they applaud him briefly. Then suddenly, the applause dies down, and a door opens in front of us. Luna guides us forwards, into the light of the mess hall.

"It is time to meet our special guests: Princess Luna, Wishbone Willow and Moonlight Shade!"