“The Dias is one of the only pieces that was actively moved over from the old castle in the Everfree. It was placed here in the principal tower, highest of the palace, as both a functional aspect and to reflect its importance,” Luna said, characteristically brusque as Twilight had come to expect. Ever since her ascension, she had been told, not asked, by the moon princess that she would enter her tutelage as well as Celestia’s.
A formality, making the previous arrangement official and nothing more.
It was not something Twilight had welcomed.
“What is its purpose?” Twilight asked. Long had it been now that when they met like this, Twilight would drop Luna’s title. And both would pretend they were putting no thought into the matter when, of course, this was yet another formality.
Twilight was doing this to get under Luna’s skin. And Luna was pretending to not be bothered at all by it.
But Twilight knew the truth. She was under no illusions that her ascension had been Celestia’s design alone, and that Luna had never been pleased by it. Her verbal inclusions of Twilight as one of them always seemed forced, drank in like a mouthful of lye, cringing and overworking of the tongue to affect an air of normality.
Sadly for Luna, subterfuge had always been her elder sister’s strength.
Twilight tried to hate herself for feeling some dark pleasure in that.
“The sun and moon are not merely there for aesthetics. The sun gives life to the entire world, its magic nurturing and cultivating. The light can help the chemistry of agriculture, but without the magic, it wouldn’t matter. Without the magic it provides, the sun would shine over a dead world.”
“I… I…”
“The moon governs the mind, in contrast to the sun’s nurturing of the body. My magic weaves throughout the nocturnal domain and allows ponies to dream. It keeps them spiritually nurtured. Without it, the moon would stand sentinel over a world of not the living, but the existing, and nothing more,”
“I… know,” Twilight spat, before falling to her hooves. She hacked and coughed, gasping for air. Luna walked over and regarded her with a look of frustration.
“I will ask you again, why do you keep doing this to yourself?”
“Tell me about the Dias, get it over with.” Twilight replied, making no request for Luna’s help and receiving no offer. The two remained locked for a moment in a silent battle of nothing more than stares, neither willing to break. This seemed to be the alicorn’s domain, battle in the conventional sense must be so trite to beings who could kill the whole world, should they choose.
Better to use words, and no words, and looks across rooms and in towers, and remaining on the floor spluttering and not helping someone on the floor coughing their lungs out.
Luna’s head tilted near-imperceptibly.
“The Dias can amplify and harness the magic of any construct, physical or otherwise. We use it with the spheres, to capture their power and change the way it behaves. Should an enemy to Equestria attempt to disturb our citizens in their dreams, I could use this to stop them. Say they tried to raze our crops, disrupt our supplies, my sister could amplify her sun’s rays and focus them on reviving the lost fields. It’s marvellous, really,” she said, her voice sounding frighteningly mortal in its reverence for the massive, mirrored surface, hovering over a deceptively small plinth.
A thought occurred to Twilight.
“Why were you arguing with Celestia? Months ago, after I’d defeated Tirek, I heard you in her chambers. Why?” Twilight asked, causing Luna to wheel around and cross the distance between them in a heartbeat.
“I will brook your attitude, little sister, but do not profess to meddle in the business of gods,” she hissed, eyes centimetres from Twilight’s.
“I thought I was a god,” Twilight replied, shaking with laughs that quickly devolved into spluttering coughs, “If what I ask isn’t to your liking then we can stop the lessons, but if you’re going to insist to keep them going, then I will behave precisely as I would with Celestia. She never shies away from a difficult question from a student.”
“This lesson is on the Dias, and you will stay on topic-”
“I couldn’t care less about your stupid mirror,” Twilight spat, maybe it was the lack of brainpower, maybe it was how exhausted she was, maybe it was seeing the facade break and see the princesses squabble like siblings, maybe it was how long since she’d seen… her friends.
But the pretence had left her, totally and entirely.
“Do you know how much you’ve taught me in these lessons? Essentially nothing. And I know you know that. I know what you’re doing, you’re hoping that by bringing me up here every other day, and lecturing for hours on end about material I already know, you’re going to break me and get me to listen to what you actually want to tell me, but it’s not going to happen. So either tell me about what you and Celestia were arguing about, or leave me in peace, because I’m not listening any more.”
Luna looked at her levelly, seemingly unmoved by Twilight’s brazen defiance. It was amazing, how much of what Twilight did recently that seemed to prove utterly, totally futile.