Charlie flicked his wand. "Aguamenti!"
A thin stream of water shot from the tip—about the width of a thumb, no stronger than a kitchen faucet.
Professor Flitwick nodded.
"You've got the wand movement and the incantation perfect. The problem isn't skill. It's intent."
The professor knew exactly why Charlie had come—to turn the water-making spell into an actual weapon. So he didn't waste time.
"You need to change what you want from the spell. Every charm was born from a need, but the same spell can serve different needs. That's where we bring in two ideas: surface needs and deep needs.
Surface needs decide how the spell looks and behaves. Take the fire spell, for example."
Flitwick gave his wand a sharp flick. A spark of magic leaped out and hit the classroom curtain. A small flame bloomed instantly.
"That's one way it can appear."
He waved the flame out, repaired the singed fabric with another flick, then held up his empty palm.
"This is another."
A fireball roared to life in his hand without warning. In one smooth motion he hurled it at the curtain. It exploded on impact, flames roaring up the fabric.
"Different form again," Flitwick said. He pointed his wand at the burning curtain and flicked downward. The fire obediently streamed down the wall and onto the floor like liquid.
He extinguished everything and fixed the damage.
"Surface needs control two things," he explained. "First, the actual shape the magic takes—like lighting something from across the room versus holding a fireball in your palm. Second, how you direct it. Left, right, up, down. All of that is still surface-level control."
Charlie nodded fast, excitement and awe mixing in his chest.
He'd always hoped the fire spell could become something brutal—like a military flamethrower. And the water spell? He wanted it to hit like a high-pressure hose. Turns out both were possible. He just hadn't understood the rules yet.
Until now.
"You really get it?" Flitwick asked.
Charlie didn't just nod. He flipped his hand and produced two chocolate frogs.
"Wingardium Leviosa."
One frog rose into the air.
He canceled the spell, focused harder, and cast again.
"Wingardium Leviosa."
Both frogs lifted this time.
"Making one thing fly versus making two things fly—that's a different surface expression," Charlie said. He kept the spell going, guiding the chocolates in lazy loops through the air. "And this is the control part."
Flitwick's eyes went wide. The boy hadn't just parroted the lesson back—he'd given a perfect, original demonstration in under two minutes.
"Excellent," the professor said after a short cough to hide his surprise. "Now let's talk deep needs. We'll use the light charm for this."
The curtains snapped shut. The classroom plunged into total darkness.
"Suppose you're a kid terrified of the dark. What kind of light do you think you'd produce?"
Charlie's mind raced.
"Something huge. Bright enough to blast the whole room."
"Exactly." Flitwick waved his wand. The room exploded with blinding white light—so intense Charlie had to squint. The professor let it fade until the space was only dimly lit.
"Now you're trying to read and the light's too weak. What do you need?"
"A soft glow. Like a desk lamp. Nothing harsh."
Flitwick nodded and pulled the curtains open again.
"Fear of the dark. Curiosity about a book. Needing just enough light to see the path ahead. Those are your deep needs—the quiet, honest reasons behind the spell. While you're busy shaping the surface, your deep needs fill in the gaps automatically.
Scared of the dark? The light spreads farther and brighter than you consciously asked for. Just want to read? It softens itself so it doesn't hurt your eyes. Lighting the way? It focuses forward instead of blinding you."
Charlie tapped his fingers on the desk, staring at the floor while the ideas clicked into place.
"So… my deep need is beating whatever's in front of me. I want the water spell to work in a fight. My surface need is making the stream come out thin and fast—like a real water gun. That's the form I want."
Flitwick clapped once, pleased.
"Perfect. Let's test it."
He raised his wand at the stone wall.
"Aguamenti!"
A razor-thin jet of water screamed out and slammed into the floor with a sharp psssht. When the splash settled, a small crater had been drilled into the stone.
"The water gun is just one combat version of the spell," Flitwick said with a sly grin. "There are plenty more useful tricks, but we'll get there one step at a time. If practicing the water gun gets boring, switch to fireballs for a while. The fire spell has even wilder possibilities."
He turned toward the door.
"Class dismissed. And don't come back until you hit a new wall with something."
Charlie stayed in his seat long after the professor left, replaying every demonstration in his head like he was tasting something expensive.
Only after several minutes did he jolt upright.
"Wait—Professor! We never even talked about the localized expansion charm problem!"