Hermes straightened up from the training dummy, tugged his twisted collar back into place, and looked Regulus dead in the eye. "Teach me."
Regulus wasn't going to agree, of course.
Magic at the level of Fiendfyre wasn't a question of knowing the spell. It was a question of whether the conditions were met.
Regulus looked at Hermes and shook his head slowly. "Fiendfyre. You're not ready."
Hermes didn't argue. No resentment either.
He wasn't about to ask then how do you know it. Regulus knowing things had long since stopped being strange.
A nod. Acceptance.
"Your spellwork itself isn't the problem."
Regulus continued. "Your output, your casting speed, your command of the Dark Arts... among young wizards, you're near the top. What's holding you back runs deeper than any single spell."
Hermes frowned, listening.
"Hogwarts teaches how to cast. Wand movements, gestures, pronunciation, basic magical control. That's the technical layer. Every student learns it. The only differences are talent and repetition. But what separates an ordinary wizard from an exceptional one isn't technique. It's mental fortitude, emotional control, focus of will, fine-tuned magical manipulation."
Regulus watched him, tone level. "Among Pure-blood families, the ones that take magic seriously begin training these things once a child is old enough. Not every family bothers."
He took two steps closer. "Some families teach nothing but social etiquette and bloodline theory. Some teach their children how to coast through careers at the Ministry of Magic. Some don't have these skills in the first place, so they can't pass them on."
Something shifted behind Hermes's eyes. A rare moment of genuine thought. His brow creased, then smoothed. "My father mentioned it."
Regulus watched him and said nothing.
Silence held.
Hermes grew uncomfortable under the stare, his gaze drifting to the wall, then back, only to find Regulus still looking at him, waiting for him to continue on his own.
He had no choice but to add: "I never trained it, though."
"Mr. Mulciber doesn't teach you?"
Hermes dropped his head. Not a word.
A muffled snort escaped from the corner. Cuthbert had a hand over his mouth, shoulders shaking. Baruk wobbled along on top of his head.
Alex pressed his lips together and turned away, pretending to study the runes on the wall.
Hermes didn't look at either of them. He stared at the floor.
Regulus understood what had happened.
The Mulcibers had practiced Dark magic for generations. Abros couldn't possibly be ignorant of Occlumency.
A family that specialized in the Dark Arts, had done so for several generations without going mad, remembered to marry and have children, and managed to raise those children to Hogwarts age... that alone told you something.
If you didn't want to lose your mind, if you wanted to be a functioning Dark wizard, Occlumency was mandatory. Abros would know it.
But he knew his son.
Hermes had talent for spellwork. He picked things up on the first try, had them down by the second, wielded Dark magic with fluency.
The mental disciplines were a different story. Hermes had no patience for anything that required sitting still and figuring things out on his own.
So Abros had probably taught him. Hermes had probably listened. Probably tried it once. Found no immediate results. Quit.
"You have two choices."
Hermes raised his head.
"Keep training Dark magic. You have the talent. By graduation you'll reach a considerable level. In the upper years, you could test yourself against an Auror."
Something flickered behind Hermes's eyes.
"Or stop for now. Train the foundations. Occlumency, magical control. Slow progress, nothing impressive to watch, tedious while you're doing it. But once it's done..." He met Hermes's gaze. "You'll be stronger."
Hermes believed Regulus, of course. If Regulus said he'd be stronger, he'd be stronger.
Still, he tried to think it through. Then gave up thinking and asked directly. "Is that how you trained?"
Regulus considered.
There was nothing wrong with framing it that way. He had trained like this. Among other things.
He nodded. "That's how I trained."
Hermes stopped hesitating. "I'll do what you say."
Then he thought a moment longer, and this time managed to produce something. His voice came out uncertain. "...Patronus?"
Regulus glanced sideways at him. "Are you happy?"
Hermes's mouth closed.
A sharp snort burst from the corner. Cuthbert hadn't held it in, breath escaping in a rush. Baruk wobbled on his head, front legs tightening in his hair, clicking his chelicerae twice in displeasure.
Alex turned away, lips pressed shut, shoulders trembling.
Hermes shot Cuthbert a glare but didn't argue.
He couldn't.
The Patronus Charm required happy memories. Intense enough, pure enough happiness.
And the Mulciber household... grim, severe, steeped in the Dark Arts.
Whether he had a memory joyful enough to sustain a Patronus was something he'd probably wondered about himself, but nobody had ever asked him to his face.
Regulus asked. Hermes had no answer.
Regulus didn't linger on it. "Patronus later. Occlumency first."
He laid out three stages, briefly.
"Identify your own emotions. Know what you're thinking right now, what you're feeling. Which thoughts are yours, and which have been pushed in from outside. Then push the emotions aside. Let them recede to the edge of your awareness. You know they're still there, but they can't interfere with your judgment. Finally, build a barrier. When another person's will touches your mind, they find no way in."
He looked at Hermes. "Master those three steps, and you can go deeper on your own."
Hermes's brow tightened. He was listening with real attention.
"These three steps share the same underlying logic as magical control. Both are about making your will dominant. Magical control means making your magic obey you. Occlumency means making your mind obey you."
He added: "For you there's an extra reason. Dark magic amplifies the caster's negative emotions. The stronger the emotion, the more powerful the curse, and the easier it is to lose control. So this isn't optional."
Hermes listened to the end, his expression far more serious than before.
It wasn't that Regulus had explained it particularly well. He simply trusted Regulus, knew how powerful Regulus was, and that made whatever Regulus said correct by default.
Regulus raised his wand. "First, let me show you how fragile your mental defenses are."
He didn't need the wand, strictly speaking. His Legilimency had reached the stage where he could deconstruct and deploy it in parts. Eye contact alone would suffice.
The wand pointed at someone was a psychological signal, letting Hermes know what was coming, letting the tension build.
Tension meant exposed weak points.
Hermes tensed.
"I won't look through your memories. I won't touch anything private," Regulus said, tone calm. "I'm going in, that's all. So you can feel what intrusion feels like."
Hermes gave a short nod.
"Legilimens."
Regulus's mental force pushed outward, slow and inexorable.
Hermes felt something press against the inside of his skull from the outside.
Instinct told him to resist, but he couldn't find anything to brace against.
In his imagination there should have been a door, a wall, a barrier. None of it existed.
All he had was a loose, untested perimeter of consciousness, thin as mist, scattering at the first breath of wind.
Regulus's will drove straight through, reaching the core of his mental space.
Pressure closed in from every direction, immense, inescapable.
It carried no malice, no hostility. Only a will vastly stronger than his own standing inside his mind, filling every corner of the space, looking at him.
Hermes's skin crawled. He felt stripped bare, seen through completely, nothing hidden.
Regulus was inside. He didn't rummage. He didn't sift through memories. He didn't touch a single specific thought.
He stood there, and his presence alone delivered the message: your defenses are nonexistent.
Then he withdrew. The entire process lasted less than two seconds.
A sheen of sweat had broken out on Hermes's forehead. His eyes were slightly glazed, his body swaying.
He shook his head, blinked several times, dragged a palm across his face as though trying to wipe the residual sensation of violation from his brain.
Regulus's voice came quiet. "Feel that?"
Hermes drew a deep breath and nodded.
"Right now your mental defenses are thinner than parchment. One touch and they tear."
Regulus lowered his wand.
"If the person standing in front of you today wasn't me, if it were anyone else who knew Legilimency, every memory you have, every intention, every weakness, would be laid out for them to read."
The color had drained from Hermes's face.
Regulus was right. He'd never considered this.
His head had always been full of offense: how to attack harder, how to cast more devastating Dark magic, how to put the other person down.
Defense, in his training, was almost a blank page.
"I'll help you train Occlumency. Regular sessions where I apply Legilimency pressure, and you learn to build barriers under active intrusion."
Regulus looked at him, laying out the training plan clearly.
"Magical control you practice on your own. Start at your fingertips. No wand, no incantation. Push magic out through your fingertips. Learn to direct its flow and regulate its intensity. Questions come to me."
Hermes nodded.
Regulus turned to Cuthbert and Alex.
"You two as well."