The attack came without warning.
Princess Celestia, Cadance, and Sunset were having tea together in the east garden when the attackers struck. They had waited until Celestia's attention was elsewhere, midway through pouring out the tea - and on cue as she tilted the pot, three crossbow bolts came hurling at Cadance from different angles.
Sunset reacted first, reaching out with her magic to block the shots - but something acted before she could to halt the attempt. It wasn't a counterspell: those were too reliant on knowing what was to be countered. This was a direct force of opposing energy, clamping down on Sunset's horn and pushing her magic inwards. Not enough to hurt from the backlash, but it quenched her magic like a match in a lake.
Cadance's training kicked in a tenth of a second later: one of the bolts was swatted downwards, digging into the dirt. The other two were coming in too fast to stop and instead slammed against the last-second shield that Cadance projected. A loud G sharp rang out as they bounced away, ricocheting into the air. In the brief time it took them to hit the ground, Cadance had already ducked under the table for cover.
Princess Celestia didn't even flinch as she finished pouring the second perfect cup of gooseberry tea.
The entire event - from the snap of the bowstring to the thudding impact of the bolts into the dirt - took three seconds.
In second number four, Sunset recognized the feel of the magic that was pushing against hers. Princess Celestia's own was unmistakable, and that's when it all clicked. This wasn't an assassination attempt: it was a test. A quick glance to the source of the shots revealed further that the three crossbows - concealed by the garden's topiaries - were set up on wooden stands and unmanned. One of the bolts was laying against the ground, revealing that it was blunt-tipped and relatively harmless. Celestia had simultaneously triggered all three crossbows, completely suppressed Sunset's (not inconsiderable) magic, hidden both actions seamlessly in the act of her lit horn holding the teapot, and never so much as spilled a drop while she did so.
Five more seconds passed before Cadance stuck her head out from cover. It was at the same time Princess Celestia finished the third cup and set down the teapot gently enough to make no sound. She smiled pleasantly at her adoptive niece. "You can come out now, Cadance. I was just testing your reflexes."
The confused look on Cadance's face was a familiar one to Sunset. To help, she plucked up one of the crossbow bolts. "The Princess was trying to surprise you and see how well you'd learned to defend yourself." She showed the offending projectile to Cadance, demonstrating that it - like so many of Celestia's other tests - had no point.
Rather than vent her frustrations at Celestia as expected, Cadance laughed. With relief, but she was still laughing. Sunset stared at her, incredulous that Cadance would brush off a fake assassination attempt. And yet Cadance did exactly that. "Oh wow! You tricked me good, Auntie!" She wiped away a tear from the corner of her eye. "That was a good one. I was so sure it was real."
Celestia smiled that frustrating, smug smile of hers. "That was the point, Cadance. It wouldn't have been a good test if you knew it was fake."
The two shared another laugh - and beside them, Sunset's temper burned hotter and hotter. She could feel her cheeks reddening and her muscles twitching as anger bubbled up through her. Another one of Celestia's tests. Another lie to make ponies dance to her commands. And Cadance was taking it as a joke! Teeth clenched tightly, Sunset's magic reached out. Not to her cup, but grabbing the teapot itself. Heavy and still full of hot tea, it was a perfect projectile to slam into Celestia's face. It wouldn't do any real harm to an alicorn, but Sunset's rage-filled mind's eye only saw the satisfaction of lashing out.
Celestia took hold of the pot as well. "Sunset, if you wanted more tea, you only had to ask." Golden magic again quenched cyan effortlessly, taking control of the crockery.
Sunset face contorted in anger.
And Celestia frowned, finally catching her student's frustration.
She set the pot aside and rose. "Sunset, please come with me."
Sunset snarled. "You--"
"Please." Celestia's tone made clear it was not a request.
Pursing her lips tight to keep from shooting her mouth off, Sunset sullenly left her chair to follow Celestia.
Cadance stood as well - only to be waved off by Celestia's wing. "I would like to speak to my student alone, Cadance."
The pink alicorn looked between the two and - finding no countermand in Celestia's even expression nor Sunset's sour one - nodded with a mixture of concern and resignation.
So the two left her at the table with the scones and cooling gooseberry tea.
They walked for several minutes, meandering through the gardens. Autumn was coming into full bloom: all around them the leaves had mostly finished turning, a bright riot of oranges and yellows. As yet the air was only a little chilly and easily fended off by a pony's coat (or a now distant cup of warm tea), but it would only be a week or two before the first touches of overnight frost.
Celestia picked up her pace slightly after they passed the entrance to the hedge maze, briskly moving through the statue garden and out the other side. There - by a placid pond surrounded by artistically placed willows - she came to a halt with Sunset beside her. Both looked out across the water towards a gazebo that sat on the pond's far side, surrounded by low peony bushes.
Silence - for a few seconds.
Then Celestia broke it. "Are you calmer, now?"
The question itself was enough to re-ignite Sunset's anger. Briefly. She let out a frustrated snort-sigh. "Yes." It was a lie.
Celestia knew it was. "You aren't wrong to be angry, Sunset. You may be my student, but Cadance is your student and I interfered with your work. I am sorry for that."
A barely restrained part of Sunset wanted to laugh in Celestia's face. An apology for breaking protocol, not for pretending to murder a pony. So typically self-righteous Celestia. Sunset didn't respond.
On the other hoof, Celestia barely stopped. "I suppose I was just being paranoid. Keeping Cadance safe is... it's important to me. From the moment I discovered her, I haven't been able to stop thinking about how vulnerable she is. She had no knowledge of magic, nor was she in any way prepared to handle Canterlot's cutthroat politics. Filling those gaps in her skills has worried me for months. I don't want to see her harmed."
"So you didn't trust me to do it right and decided to scare the daylights out of her to check my work." Sunset's mouth moved faster than her brain - but at the same time, the words weren't particularly far from what she was thinking.
"Didn't trust--" The alicorn stiffened with her shocked response - then sighed heavily as she stared into the middle distance. "I gave you the task of educating Cadance because I trust you where I trust no other. And because I know you are more capable than any other to accomplish it. Teaching Cadance from zero to defending herself with her magic in such a short period of time was a nearly impossible task. I am proud of you, Sunset Shimmer. You have proven yourself yet again and I couldn't be happier for it."
Sunset wanted to sneer and throw it back in Celestia's face. It was a lie, just like all the other lies. The jealous nag knew how much of a threat Sunset was - any talk of trust was just a sad attempt to make Sunset drop her guard.
Yet.
Ever since foalhood, Sunset had been desperate to hear those five words: 'I am proud of you'. For almost her entire life, they had been the gold medal at the end of the race. And as hearing them was vanishingly rare, each time was precious and filled Sunset's heart with joy. In a rush of serotonin, Sunset smiled in spite of her anger.
"Yet another challenge completed." Celestia smiled a little, herself. "I find myself wondering what your next shall be, now that you're finished with Princess Cadance's education."
And Sunset's smile vanished. "What?"
Celestia finally looked to Sunset, though the movement was more with her eyes than with her head. "I had assumed you would want to move on to your own projects again, now that you're done teaching Cadance what I asked you to."
Panic swelled in Sunset's heart. She was so close, and now Celestia was trying to push her away! Obviously she knew that Sunset was preparing to make a move on Cadance. That couldn't happen. "I'm not done," Sunset quickly retorted - perhaps too quickly.
Her response was Celestia raising a questioning eyebrow.
"I'm not done," Sunset repeated, her façade of control going back up again. "Cadance is still way behind where she should be, and she can't even do most of the basics of magic like a proper unicorn. I can't stop now, she's finally making some actual progress!"
Now, Celestia finally turned her head properly towards her student. "Are you saying that you wish to continue to work with Princess Cadance? As her teacher?"
It felt like a trap. Sunset was sure it was a trap. But she couldn't see how, and hesitation would kill the opportunity. Too much was at stake. So she nodded. "I demand to continue," she firmly stated.
That earned another curious eyebrow-lift from Celestia. "I see." She paused thoughtfully. "And if I refuse your demand?"
And there it was. Sunset smiled grimly as the play was revealed: it was a test of obedience. The Princess testing her student to ensure Sunset would obey commands and march as she was told. Lifting her chin and glaring into Celestia's eyes, Sunset declared her defiance. "Then I would do it anyway."
Celestia considered. Then, nodded. "In that case, I give you my blessing to continue."
It grated on Sunset: Celestia had challenged her, Sunset had fought back, and now Celestia turned it so she could claim Sunset's actions for her own. But it was hardly the first time it had happened, and Sunset had her eyes on the prize: Cadance. (The true prize was the information Cadance had, Sunset reminded herself.) So Sunset smiled through gritted teeth and bore the insult.
But she couldn't entirely restrain herself from taking a potshot. "Any orders about what to teach her next, Princess?"
Celestia's ego deftly deflected the sarcasm, and she legitimately pondered the question. "While I would like to see her learn more robust shielding spells, what she has now is currently sufficient and you're right that she needs more experience before she can handle advanced spellwork." She paused. "What do you want to teach her, Sunset?"
A fair question - but one Sunset had prepared for. Laying out plans for what to teach Cadance (and what to avoid teaching her) was something she had thought out well in advance - even if Princess Celestia's demands had derailed it. "Well, I have to fill in the rest of her basics first," she noted. "Light spells to start, probably. Then after simple things, I think I'll test her capabilities with illusions - since she seems to have an affinity with music, I want to have her try auditory alterations." A phantom of a smirk crossed Sunset's lips, knowing she had done similarly. "Vocal projection and volume control for public speaking sounds like something she would get use out of."
Nodding distractedly as she thought, Celestia looked back over the pond. "That makes sense. The Royal Canterlot Voice takes some effort to master. And then what?"
"Visual illusions, obviously," Sunset continued. "After that, probably some experimentation with basic enchantment. Things like making her own alarm clock or a reading lamp. Being able to bind spellwork to a focus should open up new opportunities. Plus of course, practice throughout to increase her levitation strength and dexterity."
Another nod. "And what about her cutie mark magic?"
A basely disguised wince - it was one of the subjects Sunset was purposely trying to avoid. "Uh. It didn't seem that important?" She scrambled to find a reasonable excuse rather than not wanting Cadance to access a magic Sunset couldn't control. "I wanted to focus on practical magic, not..." She waved her hoof vaguely in the air. "Whatever 'heart made out of crystal' means."
Celestia slowly shook her head. "You should not be so dismissive of it, Sunset Shimmer. Just because it isn't the kind of magic you have studied so hard on does not make it lesser." She stretched her hoof out, touching the tip against the pond's still surface. The slightest of impacts - and it sent a ripple outwards through the water. "A cutie mark is the core of a pony's being and of the magic inside them. The effect of it ripples--"
"Like the water does at the impact of a pebble," Sunset interrupted with a roll of her eyes as her voice flattened to a bored drone. "Yes, Princess Celestia, we've had this talk before. I understand the difference between learned and instinctive magic, and why both of them are important." She leaned forward, tapping her hoof against a different spot - then a second and a third, each sending ripples away from them. "By that logic no matter where I start, the education I give Cadance will help her with her instinctive magic. So I can teach her whatever I want and it will help all the rest."
Princess Celestia's frown gave Sunset just that little bit of joy. "Perhaps I should use a different metaphor as you are already so familiar with this one."
Sunset pressed the attack with more vigor at the Princess' faltering. "The metaphor isn't the problem, Princess Celestia. I understand what you're trying to say: I just disagree." She paused for half a breath - not giving Celestia enough time to counter but leaving enough time to let the alicorn start to think of one. Then she cut the Princess' thought process off. "Or do you not trust me to teach my student?"
It was the perfect knife - built from Celestia's own words. It dug deep, and Sunset could see the Princess' frown deepen at the knowledge she had been bested. "No." Celestia's response was slow and packed with frustration. "I trust you, Sunset Shimmer. I simply want to help provide some insight. After all, Princess Cadance may be your student but you are still mine."
Knowing it was time to retreat rather than risk further confrontation, Sunset bowed her head slightly. "Of course. Now if you'll excuse me, I really should go check up on her. She and I need to schedule our next session."
For a brief moment, Celestia hesitated - almost certainly considering refusing to let Sunset leave. But that thought passed, and she instead merely inclined her head to allow the exit.
Sunset left the Princess standing there beside the pond - alone in a garden of silent statues and dying autumn foliage.