Regulus stayed where he was, fingers absently rubbing together as he sank into thought.
Professor Sprout's words echoed in his head. Emotion wasn't precise. What was precise was nature, and magic carried its own tendencies.
And then something clicked.
After getting Verdant Magic over the holidays, he'd used Dittany's magic to heal wounds and watched the plant wither afterward. Even then, he'd vaguely sensed that magic had a kind of leaning to it.
Some of it was gentle as spring water. Some of it burned like fire.
But that still wasn't the same thing Professor Sprout was talking about. What he'd understood back then was closer to what she'd call a magic's nature.
He'd thought it was some hidden knowledge that came with the Black family inheritance. A secret only a few people ever touched.
Now he understood.
Professor Sprout had taught Herbology here for twenty years. She'd cared for hundreds of magical plants with her own hands.
She'd seen how Venomous Tentacula could leave an animal paralyzed from head to toe. She'd seen Devil's Snare stretch its vines at night and drink the life out of anything trapped inside it. She'd watched Mandrakes go from seedlings to full-grown plants, start to finish.
If anything, she knew more than he did. Far more.
He'd gotten knowledge from an inheritance and tested it until he found answers.
She'd spent decades living those answers, building rules from experience.
The tiny spark of superiority that had started to rise in him vanished in an instant.
"A seedling's magic isn't complete," Professor Sprout went on. "So the cry can only make people feel unwell, it can't kill. But the magic is already there, it's just not strong enough yet."
She looked at him, and Regulus lifted his head to meet her eyes.
Warm brown. Fine lines at the corners. And right now, a quiet meaning sat behind her gaze.
Regulus understood.
She'd seen straight through him.
She knew he'd used Verdant Magic to touch the seedling. She knew he was studying the nature of magic, and she might even have guessed he'd gained something unusual.
And honestly… good.
Verdant Magic wasn't the sort of thing he needed to hide away like a crime.
If she'd already seen it, then he could ask questions openly.
He could practice openly.
And she still hadn't exposed him. She was simply teaching, giving him the truth in the plainest way possible.
Sound was only the carrier. The real danger was decomposition itself, the nature embedded in the magic.
A seedling's magic wasn't complete, so it could only make you sick.
A full Mandrake was complete, so it could kill.
Professor Sprout's expression softened again, back to her usual warmth. "Studying the nature of magical plants' magic is a valuable direction, but it's also dangerous. Some natures, once triggered, can't be undone."
"Mandrakes are only one example. There are others like Venomous Tentacula's nerve paralysis, Devil's Snare's life-draining and The Whomping Willow's physical pulverizing."
She was warning him, and guiding him. Don't get distracted by surface effects. Understand what lies underneath. Don't touch dangerous plants casually. Build knowledge and protection first.
But it was the words themselves that struck him hardest. With each one, something in his mind cracked open a little wider.
He felt inspired, and at the same time, a faint tightness crawled up his spine.
Paralysis, Draining, Pulverizing and Decomposition.
They weren't spell names. They weren't textbook terms, at least not in the way Hogwarts usually taught them.
They described outcomes. Final states. The way magic expressed itself once it took hold.
Which meant the magic itself carried the quality that produced that state.
In this context, those words sounded less like explanations and more like concepts.
They sat beneath any single spell. More fundamental, more direct, and more abstract.
This was real guidance.
Regulus had ideas, but they'd been hazy and uncertain. Little bubbles of inspiration that popped before he could grab them.
He might have discovered this on his own one day, or he might not.
He might have wandered through a hundred wrong turns, or missed the crucial clue entirely.
And now Professor Sprout had pointed straight at it, saving him time, giving him a direction to walk toward.
Maybe it was close. Maybe it was far. He didn't know.
He only knew he would keep going.
Sometimes true teaching was only one sentence.
"Thank you, Professor," Regulus said, bowing deeply, the gratitude in his voice real.
Professor Sprout smiled, the lines on her face easing. "You're talented, and you think for yourself. Stay curious, but stay cautious. The wizarding world is vast, and some things need time before you can truly understand them."
Regulus nodded seriously and thanked her again.
It reminded him of what Professor Flitwick had said after Charms once. Magic was there. Everyone understood it differently. But you had to believe in the strength of your mind.
Different words, same core.
Don't rush, take your time and always keep your mind open.
When he left the greenhouse and started back toward the castle, he was still sorting through the conversation in his head.
And another thought surfaced.
How powerful was Professor Sprout, really?
Those natures and tendencies she'd named so easily, could she use them herself, shaping them into magic?
Or were they simply rules she'd observed and summarized?
He didn't know. But one thing felt certain.
Professor Sprout shouldn't be dismissed as a gardener who happened to teach. Her understanding of magic ran deep, and it had structure.
She had to be a powerful witch.
Professor Flitwick had pointed him toward magic's irrational side. Professor McGonagall had guided him deeper into Transfiguration's essence. Professor Sprout had shown him a direction for Verdant Magic.
Every professor at Hogwarts guided their students in their own way.
They really were good people.
He could feel their kindness, plain as sunlight, even if none of them would ever call it that.
A flicker of emotion rose in his chest, then he pressed it down.
Feelings were feelings.
What he needed was to turn that feeling into action, and turn that insight into strength.
Slughorn, old…
Dear Professor, you're the only one left.
Time to start coughing up those Galleons.
---
Friday's Defence Against the Dark Arts classroom was on the third floor. The windows faced the courtyard, and beyond it he could see snow piled along the edge of the Forbidden Forest.
When Regulus walked in, most of the class was already seated.
Cuthbert and Alex had saved him a spot in the middle rows by the window.
Hermes sat alone in the back corner, head down over his textbook.
Professor Galatea Merrythought stood at the front.
A middle-aged witch, hair neatly combed, deep gray robes, and an expression that always seemed a bit too dramatic for whatever she was saying.
"Today we're covering two things," Professor Merrythought announced, opening the book.
"First, the Red Sparks. The incantation is Vermillious. It's used to send up a red signal light. If you're lost or in danger outdoors, it lets you warn your companions."
She wrote the incantation and pronunciation on the blackboard.
"Rotate your wrist like this, wand tip up. When you cast, picture red or green light spraying from the tip, then maintain the spell."
She demonstrated. A fist-sized red orb of light bloomed at her wand tip and floated in the air, casting a soft red glow.
It held for three seconds, then winked out without leaving a trace.
"A safety charm. It won't cause harm," Professor Merrythought said. "Now pair up and practice."
Students started practicing. Cuthbert paired with Regulus again, as usual.
Regulus succeeded on the first try. The orb was clean and standard, the color pure, the duration precise.
But his focus wasn't really on the exercise, because another thought had already started chewing at him.
Light magic.
Light was wave and particle at the same time, a form that carried both properties.
Red was because the magic's frequency…
Regulus stopped himself.
No.
He decided to try a different approach.
Don't think like that. Don't think about duality, don't think about frequency. Think about magic.
If it wasn't only light, what if light could carry information?
Light already carried information. And sometimes information could be a weapon.
Or what if light could become physical, packed with energy, and then explode?
He could give it symbolism. Give it meaning.
Light as warmth.
Light as protection.
Light pushing back the dark.
And then his mind drifted even further.
Light as the light of civilization.
While those thoughts scattered through him, his hand kept practicing on autopilot. The orb flared again and again, appearing, hovering, fading.
Half an hour later, Professor Merrythought clapped her hands to stop them.
"Second topic. Gnomes." She flipped to another page.
"Gnomes are magical creatures. Average height, thirty inches. Pointed ears. They like stealing and eating magical plants. They're common in gardens and courtyards, and they're pests."
The book included a simple sketch and an anatomy diagram, made for young witches and wizards to understand.
"To deal with gnomes, you use the Gripping Charm. Cast it, grab the gnome, spin, and throw it past the boundary."
She repeated the incantation and showed the movement, but didn't demonstrate.
"Next class we'll do a practical, clearing gnomes from the Hogwarts grounds. Today is theory."
A low cheer went up across the room.
Practical lessons were always more fun than theory, especially in Defence Against the Dark Arts, a subject that should have been exciting and somehow managed to be dull.
A few Gryffindors were already whispering about how to throw a gnome the farthest. The Slytherins were more restrained, but even they wore looks of anticipation.
Regulus wasn't particularly interested.
A gnome was low-grade. It had about as much combat value as nothing at all. The only annoyance was their numbers, how fast they ran, and how good they were at burrowing.
Compared to everything else on his plate, it barely registered.
And the new ideas he'd just had would have to wait.