"Whoa."
To be fair to Cadance, it did look pretty neat. Her baby blue magic was holding a half-dozen lit coals in the air, each bobbing as if in water. The charcoal - despite hovering at head height - continued to burn merrily and Cadance could only stare in wonder.
It was an exercise derived from their previous session: Cadance had laughed about her awkward attempts to juggle using magic, quipping that Sunset's next step up in difficulty would be to set the balls on fire. She hadn't believed it - or at least vocally doubted - when Sunset informed her that a unicorn's magic aura didn't transmit hot and cold sensations back to the caster.
Now she believed it, because she was holding fire and remained unburned.
"Technically," Sunset lectured, "Your magic doesn't even have a sense of touch. It's more how the field can tell where it is and isn't when it pressed against an object, and your brain interprets it the same way as if you had the item in your hooves. But on a technical level, the senses are completely different and that's why you're missing things like hot and cold. You also couldn't tell if something covered in honey was sticky, for example."
Cadance slowly rotated one of the coals in the air, watching as the flame turned to remain upwards even as the fuel spun around.
Sunset tried not to smile. "Okay, so you're a moth now?" A quick swipe of her magic scooped the coals away from Cadance. "Come on, we've got work to do and nothing's getting done if you're going to be hypnotized by the nearest light source." She levitated the coals into the brass brazier she brought before capping it to extinguish them.
She had borrowed the Royal Guard's practice chamber again - albeit this time for a different reason. The wide open space of cool stone normally provided room for guards to perform combat magic in a controlled environment (and one that was made of strong enough material to withstand an errant blast or two), but this time Sunset wanted it mostly for the broad, domed shape.
"So today we're going to progress past raw magic and into actual spells." Sunset motioned for Cadance to move, positioning her in the dead center of the sparring ring and of the larger dome. "Since you seem to have some kind of talent with music, I thought we'd start with auditory illusions."
Cadance's head tilted. "I thought illusions were images."
That misconception was dispelled with a shake of Sunset's head. "The term covers all sensory magic, technically. Visual is the most common, but auditory's a close second." Reaching the edge of the ring, she paused to set down the brazier before returning back to her student. "The others are a lot more niche, though. Taste illusions are pretty much limited to bad restaurants and parents with foals that are picky eaters, smell requires a lot of magical power to get any practical effect so it's rarely used, and nopony has really figured out touch." She shrugged that little challenge off. "Anyway! None of that's important right now. The idea here is that I want to teach you how to do a repeater spell."
"Repeater spell?"
Sunset stepped closer, drawing up beside Cadance. The conversation paused for a moment as Cadance ambushed her fillyfriend with a brief nuzzle. "Uh, yeah. Repeater spell," she repeated. Sunset recomposed herself and tried to pretend she wasn't blushing. "The idea is that you can make your voice heard somewhere you aren't and possibly when you aren't speaking."
Comprehension lit in Cadance's eyes. "Oh! Ventriloquism!"
"Sort of," Sunset hesitantly allowed. "Why I wanted to teach you is so that you can kind of mimic how Princess Celestia has the Royal Canterlot Voice. You can't shout like that, but you can make it so that when you speak the words get repeated elsewhere. Then ponies won't have to strain to hear you when you're giving a speech because it'll seem like you're right next to them."
It was a practical spell for a public official or royal scion: Cadance would absolutely be forced into public speaking events and the like. Anything that could give her an edge would help and right now the pink princess needed every one she could get. Just Sunset's use of the word 'speech' had struck the alicorn dumb, purple eyes locked wide with fear.
Sunset leaned her head against Cadance's in a clumsy nuzzle of her own - enough to snap the alicorn out of her shock. "We'll take it slow, okay?" The responding nod was rabbit-quick, but it was there. "So step one: light your horn."
Closing her eyes to concentrate, Cadance did so.
"Step two," Sunset continued gently, "I want you to direct the magic inward to your throat. Like swallowing a big gulp of water."
The mnemonic took easy root and Cadance swallowed a mouthful of air. The baby blue glow of her horn stayed at the same intensity, but a similar (but more muted) glow coalesced around her throat.
"Good. Step three: Sing a single note. Any note," Sunset quickly added. "And project from your horn at the same rate you breathe out."
Cadance hesitated for a moment as she parsed the command - then she sang a simple tone. Formless, wordless, but even and strong. As she tried, the magic around her horn flickered like a candle before winking out. The tone went nowhere before dying off as Cadance ran out of breath.
Frowning, Sunset thought. "Hm. Alright, let's try again. A lot of unicorns use a guide-word to focus the spell, but with your raw alicorn power you shouldn't need to." For a moment, she pondered. "This time I want you to..." She paused again, struggling to translate unicorn instincts to the thoughts of a non-magical pony's. "You need to concentrate on both places in your body at once. It's like crossing your eyes. You have to maintain the magic both in your horn and your throat."
It took several minutes worth of tries before Cadance was able to strike the right balance and keep the energy in the appropriate places. Once she could, Sunset continued. "Step four now. Do it again, but as you sing I want you to project. But don't just project outwards, do it specifically at the brazier. Close your eyes and picture it, then focus on your voice being at that point. Like if your mouth was there rather than on your face."
With a slight nod, Cadance tried. Light her horn. Take a deep breath of air and gulp it down like water. Sing a single note. Picture the brazier.
The doppler-like effect of her own voice coming from a different location a millisecond late spooked Cadance - she lost focus on both the magic and the note as both ended with an audible fizzle. She wasn't dissuaded, though - instead looking to Sunset with bright, eager eyes.
The unicorn pursed her lips, trying not to laugh at the eager cheer. "Yeah, that was you. Try doing it again."
She did - light horn, swallow breath, sing, close eyes, focus on the point - and once more Cadance's voice rose from a spot several body lengths away from her. This time she was able to hold it as she opened her eyes and stared at the point before happily cantering in place at her success.
Sunset didn't hold back her smile. "Well done." She gave out the praise far more easily than Princess Celestia did. (It would have been hypocritical otherwise.) "I guess I was right that you've got a talent for auditory magic. That didn't take long at all."
Cadance's tune stopped as she beamed her brightest smile. And when she opened her mouth to express her joy...
Well. She had spent the last twenty minutes swallowing mouthfuls of air.
A belch exploded from a spot just over the brazier that echoed even louder in the domed room.
Cadance instantly turned bright red.
Ten tense seconds passed before Sunset finally gave in and snorted a little chuckle. That, in turn, prompted Cadance to start snickering. It took only a few more moments before both of them were on the floor laughing outrageously in a loose hug.
After several good minutes of laughter, they calmed enough for Sunset to speak up. "Well, I was going to warn you eventually about remembering to turn it off to avoid, uh, unintended vocalizations but I guess that's as good an object lesson as you could have."
And that sent them both into childish giggling again.
This time it passed a little quicker. A little.
Recomposing herself once more, Sunset tried to veer them back on track. "We'll have to practice it a lot more, but I think you understand the basics. Eventually you'll be able to have your voice project from multiple locations at once, amplify it, or even have it replay on a delay. It can't help you hit the volume Princess Celestia does but if the sound is coming from every place around the edge of a room, nopony will have a problem hearing what you're saying when you give a speech."
The mention of speeches visibly threw a bucket of water on Cadance's good cheer - in a flash, she went from giggles to a somber frown. But a thoughtful one, and a moment later she asked a seemingly non-sequitur question. "Sunset, does the spell only work with your own voice, or could you project other sounds?"
"Other sounds are pretty easy. This spell's actually the basis of a lot of stuff." Sunset didn't consider the relevance of the question, falling directly into teaching mode and thus missing the blatant change of topic. "Most enchanted items that make a sound are derived from this spell. Like if you ever see a loudspeaker at a concert, the enchantment powering it is using pretty much the same thing I just taught you."
Pressing a bit - and leaning into Sunset - Cadance followed up. "So like radios?"
Sunset quickly shook her head as her inner nerd took over. "Radios actually use a related spell called Crystal Clarity's Clear Communication which is based off of a telepathy spell, but close enough yeah."
Instantly, Cadance's grinning face was right in Sunset's, startling the unicorn backwards. "So you could cast that spell and just have a radio any time you wanted? Like you could do it right now?"
On one hoof, that wasn't the lesson and a radio spell was far too advanced for Cadance's barely passable skills. On the other, Cadance had used the phrase 'you could do it' and Sunset immediately interpreted that as a challenge. So it was no surprise when Sunset's horn lit. Eyes closed, it took her several seconds to 'tune in' properly and find a signal but when she did? The bouncy strains of Big Bop's Cantilly Lace started playing from the air just over Sunset's horn. A wave of her head sent the sound's source flying - orbiting the room to show off to Cadance just what was possible. After a full circle, it split into four different sources around them, echoing in a wide surrounding of sound.
Throughout it all, Cadance clapped giddily.
When the song ended, Sunset took a small, playful bow. Before she could cut the spell, however, Cadance grabbed her up. "Wait!" There was a moment of dead air before the next song began: the gentle piano opening of Suede Shoes' The Best Is Yet To Come. As the big band horns kicked in a few second later, Cadance's manic smile widened as she pulled Sunset towards the center of the ring again. "Dance with me!"
Sunset froze, Cadance's declaration stunning her as she so often did. "Uh."
Another tug as the alicorn tried to get them started. "Come on!" Her bright beaming smile gleamed much like a bug zapper to a moth.
The music winked out of existence as Sunset drooped. "I, uh. I've never actually danced before."
Cadance's expression fell to confusion. "Wait, really? There's four million balls and galas in Canterlot every year, and you don't know how to dance?"
The phrase 'you don't know' triggered a flinch that momentarily twisted Sunset Shimmer's face in pain.
"Princess Celestia didn't teach you?" Cadance's incredulity rose with every syllable.
Shamefaced, Sunset shook her head. "No. I-- She never dances, even at the balls. I questioned her about that once when I was a filly." She frowned, eyes focused off in the middle distance as she dredged up the old memory. "I asked her why everypony else at the party was dancing but she wasn't. She just smiled that..." Sunset fought the urge to say 'sad', but couldn't think of a better adjective for the memory. "That smile of hers and said 'My shoes are too tight, and I have forgotten how to dance.' I didn't understand what that meant and I still don't, but she obviously didn't think dancing was important, so I didn't think dancing was important. And I never bothered to learn." She ended with a lame half-shrug.
Cadance gripped Sunset's hooves all the harder. "Then it's time you did. And after I teach you, I'm going to teach her."
The somber moment was broken by Sunset's quiet snicker at Princess Celestia being anypony's student.
Baby blue magic grabbed Sunset by the fetlocks and pulled her up. "I'm teaching you first, though. We'll start with a simple upright slow dance so you can follow along with me easier. Hooves here and here," she commanded as she positioned Sunset upright and balanced against each other, with one hoof on each other's hip. "I'll lead so you can get used to it and watch my steps." She leaned closer, tapping the tip of her horn against Sunset's. "If you wouldn't mind tuning your magic radio to something slow we can practice to?"
The room was filled with static for a moment before Sunset's horn tuned away from Suede Shoes. It warbled indistinctly for a moment before the echoing room was filled with the gentle strings of Carol Martelé's Octavia Suite, composed to celebrate the birth of her granddaughter.
Cadance took the first step, slow and firm. Sunset copied her movement - and the alicorn smiled. "By the way," she commented as they danced at a snail's pace, "You might want to pick up a few books and study. I plan on making you dance with me at the New Year's Gala. Better be read~y," she sing-songed.
It was a threat.
And Sunset focused even harder on the steps, because she had less than six weeks before she had to not embarrass herself in public.