The night had long since fallen when Celestia, Luna and Stella emerged on to the roof of the watchtower. The sight was breathtaking. Here, in the heart of the Crystal Empire, the stars had a vibrancy not found anywhere in Equestria. Clearer. Sharper. Closer.

‘Always so gorgeous’, Luna said. ‘Each night Destiny makes, I envy you for that spectacle.’

Stella smiled. ‘One good reason for living up that north’, she answered. Pointing towards one of the angles, ‘You can use the telescope to indulge your curiosity’, she added, ‘but I might have something more captivating for you. Come and follow me.’

She padded towards a marble basin, propped up by four exquisitely carved silvery legs.

‘This wasn’t here the last time we came’, Celestia remarked.

‘Indeed’, Stella said. ‘Let me introduce you to “Stella’s mirror”. That’s how it was clept by the student who crafted it.’ 

Luna bent over, but only saw her own face and stars reflected in the still water. ‘What is its purpose?’ she asked, straightening up.

‘Mighty dwimmer slumbers in the water,’ Stella explained, ‘but it won’t awaken unless I utter the right word. Once awoken, the mirror may show the past, present or future, though there is no telling which. Would you care to try?’ 

‘I prefer not’, Celestia answered. ‘Each day its burden. It is vain to grieve or rejoice in things to come, which may never come to pass.’

Stella’s questioning eyes hopped from Celestia to Luna.

‘I shall try’, Luna said.

Stella smiled. ‘I was certain you would’, she said. ‘Sit comfortably. Don’t disturb the water. And remember! Things you see will not necessarily be.’

‘Understood’, Luna answered, nodding. She bent again. She heard Stella whisper a word she didn’t understand. Suddenly the water went black, and that blackness pounced at her, and she sunk into nothingness.

‘Thou shalt have dominion over moon and night sky.’ A voice — her father’s voice — said.  Looming from the darkness she saw the foal she once was trotting alongside her father in full regalia.

‘But Dad, I don’t care about moon or night. I want sun and day, like Celestia!’ Luna protested in her tiny childish voice.

‘This is, alas, not possible’, Dad replied. ‘That which is given cannot be taken back or shared.’

‘But—’

‘There is no “but”, darling. Cosmic laws bind everyone of us. In time, thou shalt realise that thy realm is far greater than thy sister’s.’

‘But…’

The shapes dissolved into the void, replaced by a muffled incantation, like a single word endlessly repeated. A vision formed, that of a lone black figure sitting atop a high cliff under a fiery sky. At its foot stood rows upon rows of tethered ponies, hooves cuffed, heads down. They were chanting, or praying? Luna was dragged steadily closer to the prisoners, flying low over each one until she finally slowed and stopped — Luna gasped — above the bony, flayed and misshapen body of Stella herself.

She tried to yell but with a puff of smoke the vision vanished and she was back in pitch darkness.

And yet she was not alone anymore. She felt a pervading presence. Emptiness itself had become alive and intent. She shuddered. Panic, abject fear, overwhelmed her, but she was rooted to the spot.

From nowhere a gruff voice, like a mockery of her own, whispered amidst the void: ‘Hello, darling! I know we haven’t been acquainted yet, but now that you have freed me, I promise I shall be with you anywhere, anytime.

Don’t be afraid! Embrace me, and I shall save you and banish the pain you’ve been bearing deep inside all these years. Together, we shall be invincible.

I have little time now, but soon we shall meet again. Till then, remember: ’Tis better to rule in heaven, than to serve in hell. 

So long, my beauty!’

The voice changed into laughter. Luna desperately shook herself loose… and found herself looking into the pool of clear water. She was sweating profusely.

‘What did you see?’ Stella asked, concerned.

‘WHO DEVISED THIS?!’ Luna shouted. ‘WHO?!’

Stella took one step back in surprise. ‘Why, his name is Swartcoat. A very promising student. Brilliant, but meek and very bashful. I have a hard time preventing the others from bullying him because of his physical peculiarities. I think they gave him a nickname… what is it? Hmm… Oh, yes, they call him “Sombra”.’