I wake up screaming in my bed. The moon has risen above the horizon, but not above the tree line here in the northern stretch of the Everfree Forest. I try remember what my dream was about, and slowly it comes to me again.

I had dreamt about that final time with my old mistress Nightmare Moon, after she had been turned back into Princess Luna. I had tried to convince her that Princess Celestia was still the enemy, but she would not listen. Even after the thousand years I spent with her on the moon, she ignored my pleas and told me that time had changed. When I tried to use magic to show her that she was wrong, I was blasted into the wall and my back leg was injured. Just as it had happened a year ago.

Then I remember a stallion whispered to me, "It is not too late to change the world." Those words send shivers up my spine.

I feel cold. Not just because my home is literally falling apart, but because of that last whispered sentence. I am not sure that it was part of the dream. It feels connected, yet not fully. It is something else, something potentially sinister.

I use bat pony magic - yes, we can use magic without horns - to cast a homely light around the bedsit. My eyes adjust to the new light and I jump out of the bed, my magic still not warming me up. Breakfast awaits: fresh fruit from the Everfree Forest. I can hear other bat ponies already outside, either picking fruit or trading it with other ponies.

I fly out of the hole in the roof that I have fashioned into a skylight, and make a beeline to the first ghost apple trees I can see. I examine each fruit for any sign of disease or damage but all of them are fine. I pick the ripest one and my large fangs sink into it, sucking out the juice. I enjoy the rest of the apple, then head to the workplace and residence of Wishbone Willow.

Wishbone Willow is a curious bat mare. She has a natural talent for dreamwalking, visiting the dreams of others while she herself is asleep. Quite frankly, it unnerves me, but I like Wishbone and we are great friends. She is even teaching me how to dreamwalk, and I am slowly becoming less afraid of it.

I knock on the door of Willow Practice, and she answers immediately. She says happily, "Moonlight! What can I do for you?"

I walk in and shut the door, sinking into an armchair. "I've been having weird dreams," I explain to her. "It's been happening for about two weeks now. Not every night, but frequently. It got much worse yesterday."

"Do you want to explain it, or should I have a look myself?"

I know what she is getting at. Alarm bell scream inside my head not to let her, but I want to find the root of my problems. There is only one other pony who I know can dreamwalk, and it took six immature slaves of Celestia to make her betray me. So I tell her, "Dreamwalking. It's easier for you to find out exactly what's happening that way."

"Fair enough. If you want to stop, tell me." She sits in the armchair opposite me. A golden magical aura forms on her forehead and snakes over to mine. We fall asleep in seconds.

I find myself stood at the edge of a cliff, Wishbone by my side. A river flows below us, and I feel unsafe. I bite my lip and take a step away from it.

"Wish, I'm not sure..." I trail off.

"Show me when you're ready."

I understand what she means, but I don't want to. "Wake us up, Wish. I can't show you."

"It will be fine, Moonlight. I am here. You have to show me. It's the only way to find out why you're having nightmares."

Cold fear courses through me, and I don't have a say in when to start, because I see a reflection of my memories on the surface of the water: flying through the forest in sadness and anger, trying to escape from Princess Luna, cursing the Elements of Harmony and Princess Celestia. I have changed, obviously, but the memories hurt. I still haven't forgiven Celestia and her minions who got rid of the Nightmare Moon I knew, the kind mare who kept me alive.

Then I hear hoofsteps, and both Wishbone and I turn around instinctively. A dark grey unicorn stallion looks at us, his red eyes glowing, a green mist beginning to form around them.

"Moonlight," he says. "My name is King Sombra. I want to help you, but I need your help too."

"Get us out of here," I say to Wishbone.

She casts a spell, and everything goes black. A storm rages and I can't see Wishbone. I can hear Sombra shouting to me, "I want to help you! What you did and what you believed, none of it was your fault! It was Celestia's fault! She hurt you and Luna so badly! Please, if you join me..."

I notice two red eyes glowing in the dark, that sickly green magic flowing away from them. I barely catch his last words.

"All of your dreams will come true."

I bolt upright in the armchair and Wishbone glares at me. "That was not cool," she snaps.

"What did I do?" I ask, perplexed. "None of that was my fault!"

"You made me see some stuff that I'd much rather forget in that river. And you saw it all."

"I saw nothing, I swear. I only saw what happened to me after Nightmare Moon was gone. The only stuff I saw was in my past. What about that Sombra pony? He said he was a king."

"Do you remember the Crystal Empire?" She's still hurt, but she hides it well and I push my guilt away.

I think for a moment. "I remember Luna saying that it disappeared."

"He was the old ruler of the Empire. Tyrannical, he was. Celestia and Luna banished him to who-knows-where and the whole Empire went with him. If there are new ponies representing the Elements of Harmony, Celestia and Luna's connection with them will fade, which could, hypothetically speaking, weaken or undo the spell that was cast on Sombra and the Crystal Empire, causing both to return to the Frozen North. If this is the truth, then he will want more power. He uses dark magic, which has the power to influence ponies through their greatest fears..."

"No!" I shout as the realisation dawns on me. "Stop lying! This is impossible. I have trusted you to help me, and then you say that the Crystal Empire has returned and it's crazy ruler King Sombra wants to use me of all ponies to regain power?! Oh my Celestia."

"Moonlight, I'm only guessing, but it's the only explanation I can find. That dream was unlike anything I have seen. Please listen to me."

"No. You're a liar." I jump out of my seat and fly out of the front door, away from Wishbone Willow. I head north, hoping that I can see some proof for or against Wishbone's theory. I fly above the forest canopy, but I don't see anything for an hour at least. I've almost given up when I notice the ice blue tower in the distance, and the way that its colour scheme makes it almost invisible.

Then those colours shift and become darker, more menacing. Storm clouds roll in and amongst the thunder, a menacing laugh rings out through the countryside. It sends me flying back home and wishing that I hadn't called my best friend a liar. Dread grows inside me, and with it the feeling that I will never escape King Sombra.