With the method confirmed, he let the parallel minds work.
This was what he had been waiting for — the one piece he had held back while he was doing the first two spells by hand. Now that he knew the imprint process was safe, that the spell construction produced no ill effects, that both Lyra and Clara had received their first spells cleanly, he could move.
He ran the spell construction across all twelve threads simultaneously.
Ten spells for each of them. He had thought about the list carefully beforehand: one for each base element, a balance of useful and foundational. Fire Bullet — small, directional, low mana cost. Water Bullet, the offensive cousin of the water ball. Air Bullet, fast and precise. Earth Bullet, slow but solid. Light Heal — basic regeneration, the kind of spell that closed small cuts and reduced bruising. Shadow Slash, which he included for Lyra and thought twice about for Clara before including it anyway because fairness mattered and so did having options.
Then the household spells: Waterball for filling buckets. Ember for fires. Wind Clear for sweeping dust. Earth Pack for tamping down loose soil.
Ten spells each, assembled in the time it would have taken him to build one by hand. He checked each finished product with his main thread before filing it for imprinting — not as thorough as the single-mind construction, but sufficient. These were simple spells and he knew them well.
He sat both sisters down in the yard.
'This is going to feel like the last one,' he said, 'except longer. You'll see all of them in sequence. Don't try to process them one at a time, just let them land.'
'How many?' Lyra asked.
'Ten each.'
Clara sat up straighter.
'Are any of them more exciting than a water ball?'
'Jeez picky much? You know that this is likely the first time in history that anyone was able to teach magic shortcuts to someone in 20 seconds right? I don't feel very appreciated as your teacher.'
'Ugh your right great master. Please grace this humble student with your lessons Great and Holy One.' She folded her hands in her lap with the most polite smile Arthur ever scene.
'For some reason, the thought of having you as a student is even more disturbing..' Arthur refocused on the task at hand.
He imprinted them.
Both sisters went still at the same time, eyes unfocused, the specific absorbed quiet of people watching a very fast dream. It lasted longer than the first time — about ninety seconds — and when they came back, they came back with the specific quality of people who had just been handed something and were immediately looking for somewhere to put it.
They both stood up at the same time.
Arthur leaned back and waited.
◆ ◆ ◆
Training started the next morning.
The format was simple: they went to the far end of the east field where nothing important grew, and they cast spells until they couldn't cast anymore. No technique instruction, no theory — he had already given them the theory in the imprint, built into every spell. What he wanted now was repetition. Cast, rest, cast, rest. The mana reservoir grew the same way the body grew: through being used past its current capacity, allowed to recover, and used again.
He had explained this to both of them the night before.
'So we're doing this until we pass out?' Clara had said.
'Until you're close to passing out. Then I refill you and you keep going.'
'You can do that?'
'Yes.'
'And this makes the reservoir bigger?'
'Over time. It's not fast. But it's the second fastest method available.'
'What's the fastest?', Clara asked. Arthur thought about how he would explain how killing monsters makes him exponentially stronger and how he doubted if this was even applicable to other people besides himself. 'Hm, your not ready for that yet. For now just focus on this method.'
Clara had thought about this. 'If I had a bigger reservoir I could cast more spells.'
'That's the idea, yes.'
'Then let's start tomorrow.'
Lyra had agreed without discussion, which was how he knew she had been waiting for this for longer than she let on.
The first morning was chaos in the best sense. Both of them working through the new spells in roughly alphabetical order of whatever they could remember, the yard filling with the specific noise and light of two people discovering what their magic felt like in practice rather than in theory. Air Bullet snapped through the air fast enough to leave a sound behind it. Earth Bullet hit the fence post with a satisfying thud. Light Heal, which required a small wound to demonstrate, Clara cheerfully provided by scraping her palm on the fence before Arthur could suggest a better option.
The heal closed it in about eight seconds.
Clara stared at her palm.
'Again,' she said.
'You're not scraping your hand again for the sake of — '
'I won't. I just want to cast it again.' She held her hand out and cast the spell at nothing. The warm golden light ran across her palm and she watched it with the specific satisfaction of someone who had found a thing they were good at and was confirming the fact. 'It feels nice.'
Lyra, across the field, was practicing Water Bullet against a piece of old fence post she had propped up against the hedge. She was doing it with the systematic focus of someone working through an assignment — ten casts, rest, ten casts, rest — and she was already noticeably more accurate at the end of the first morning than she had been at the start.
She had always been a quick learner. Apparently that extended to magic.
◆ ◆ ◆
By the third morning Tsuki and Kiiro had opinions about the training.
Specifically they had the opinion that training was happening and they were not involved, and they expressed this by positioning themselves in the middle of the practice field and looking at their respective owners with the alert, expectant posture of students waiting for class to start.
Lyra laughed.
'Do they want to practice with us?'
Arthur looked at Tsuki, who was sitting at attention with her silver-tipped tail moving in a slow patient sweep, and at Kiiro, who was somehow managing to convey intense readiness while remaining completely motionless.
'Apparently.'
'Can they? Do the spells work for them?'
'Yes. The same spells you have, actually, plus considerably more. Their magical control is — ' He paused, looking for the right word. 'It's built in. They can already do these spells perfectly.'
Lyra looked at Tsuki. 'So why do you want to practice?'
Tsuki looked back at her with silver eyes that expressed, very clearly, that she was here to keep Lyra company and if Lyra would prefer she didn't, she was welcome to say so.
Lyra's expression melted immediately as she cleared her throat. 'No — no, please join. Please.'
Tsuki stood, stretched with the total commitment of a creature that stretched properly or not at all, and trotted to a position beside Lyra with the settled air of someone who had correctly anticipated that this would be the outcome.
Kiiro was already beside Clara, sitting upright, watching the fence post.
'Right then,' Clara said to her. 'Water Bullet. Show me how it's done.'
Kiiro turned to the fence post. A precise, perfectly spherical ball of water appeared at the tips of her small snout, accelerated smoothly, and hit the center of the post with a crack that split it down the grain.
Clara looked at the two halves of the fence post. She looked at Kiiro.
'That was — that was more than a water bullet.'
Kiiro looked at her with the calm satisfaction of a creature that had been asked to demonstrate and had demonstrated.
'Arthur,' Clara said.
'I built them with perfect control,' Arthur said. 'I didn't say anything about restraint.'
'She split the post.'
'I see that.'
'A water bullet split a wooden post.'
'She applied it correctly. The spell was working as designed. The difference between yours and hers is precision — yours scattered, hers focused to a point.' He looked at the two halves. 'Which is also, incidentally, what I am trying to teach you. So. Again.'
Clara looked at the split post. Looked at Kiiro, who had already returned to her ready position with the patience of someone prepared to do this all day.
'You're a show-off,' Clara told her.
Kiiro's ear flicked once. Not a denial.
◆ ◆ ◆
They settled into a rhythm over the following days.
Mornings in the east field, working through the spell list. Arthur sat on the fence and watched and gave occasional specific corrections — angle on the Air Bullet, draw rate on the Heal, the slight overcast Clara had with Fire Bullet that was wasting mana without adding power. Neither of them improved dramatically in a single session. Both of them improved visibly across sessions, which was how real improvement worked.
When a reservoir ran low — and he could feel it from a distance, the small quiet signal of someone approaching their limit — he would walk over and refill them. The transfer was simple and quick: a thread from his pool to theirs, enough to fill the gap, done. Both of them had learned to recognize the feeling of it and stopped being startled by it after the second day.
Their pools were growing. Slowly, as he had told them, but measurably. He tracked the baseline at the start of each session and noted the increments. Lyra's was expanding slightly faster, which he thought was the light affinity making itself known — something in her reservoir's nature was efficient, drawing and replenishing at a rate slightly better than average. Clara's was growing in bigger steps but less evenly, which fit what he knew about fire-adjacent mana: it liked intensity more than patience.
Tsuki and Kiiro trained alongside their respective owners every morning without fail. The fact that they had nothing to improve on was clearly beside the point. They were there. They cast their perfect spells with their perfect control and occasionally glanced sideways at their humans with the expression of companions who were keeping someone company, which was its own kind of thing.
On the fifth evening, walking back to the house in the late light with both sisters tired in the specific satisfied way of people who had worked hard at something worth working hard at, Lyra fell into step beside him.
'What's next?' she said.
'After you can do these ten in your sleep, I teach you ten more.'
'And after those?'
'Ten more.'
She nodded, walking beside him in the evening quiet. Tsuki was running ahead, looping back, running ahead again in the aimless pattern she used when she had energy left over.
'What about the affinity thing?' Lyra asked. 'You said you could feel something in mine. When we did the diagnostic.'
He glanced at her. 'What made you think that?'
'You made a face.'
'I didn't make a face.'
'You did. A small one. You do it when something is interesting and you're not ready to talk about it yet.' She waited. 'Is it bad?'
'No,' he said. 'It's not bad. It's — I'm still working out what it is. I have a theory.'
'Will you tell me when you know?'
'Yes.'
She accepted this with the patience of someone who had learned that Arthur's yes meant yes. They walked the rest of the way in quiet, the house warm and lit ahead of them, the east field behind them marked with the specific evidence of a day well spent.
Tsuki, at the door, was already sitting and waiting for Lyra to open it.
Clara pushed past both of them.
'I'm telling Dad I did five hundred casts,' she announced to no one in particular, going straight for the kitchen.
'You did three hundred and forty,' Arthur called after her.
'Three hundred and forty is a lot!'
'Then tell him three hundred and forty.'
'Fine. Three hundred and forty.' A pause from inside the kitchen. 'Dad, I did five hundred casts today.'
Arthur stood in the doorway and thought: I am going to have my hands full.
He went inside.