Harry Potter and the Silent Guardian

After the intense Wizengamot meeting, Harry had no time to rest. Arcturus was determined that Harry wouldn't waste any precious moments. Following a few brief praises of Harry's performance, he began tutoring him in Dark Magic.

"Voldemort's return leaves us little time," Arcturus explained grimly. "You need to use every available moment to learn and become stronger."

Early the next morning, Harry found himself descending into the Black Castle's underground ritual chamber—a vast space dimly lit by floating orbs of blue fire. Ancient stone walls surrounded them, their surfaces carved with protective runes that seemed to pulse with contained power.

"Dark magic," Arcturus began, his voice echoing slightly in the expansive chamber, "is not inherently evil, merely dangerous. It's like handling raw lightning—immensely powerful, but it can destroy the wielder if proper precautions aren't taken."

With practiced ease, Arcturus activated the protective wards around the ritual circle. Harry recognized some of the symbols from Voldemort's memories: ancient Egyptian protections against magical backlash, Norse runes for mental shielding, and Greek bindings to contain wild magic.

"We'll begin with blood magic," Arcturus continued. "It's one of the more stable branches of dark magic, though still treacherous if mishandled." He withdrew a small silver knife, its blade etched with flowing scripts. "Three drops of blood, no more. The number is crucial—magic loves symbolism, and three represents catalyst and change."

Harry accepted the knife, making a small cut on his palm. Three drops of blood fell onto a specific point in the ritual circle, causing the silver lines to flash crimson momentarily. He watched intently as Arcturus began the incantation.

"Blood carries intent," Arcturus explained. "It remembers what you've done, what you've suffered, what you've overcome. Dark magic feeds on these memories and emotions. But you must control them, not let them control you."

That entire first day was spent mastering a blood-based shield charm. Unlike the standard Protego, this shield drew power from the caster's very life force, making it nearly unbreakable—but at a terrible cost if maintained too long. Harry struggled to balance the immense power with the draining effect it had on him, but under Arcturus's guidance, he began to grasp the fundamentals.

The following day introduced a new lesson. "Today, we'll explore emotion-based magic," Arcturus announced after Harry had made progress with the shield. "These spells require intense feelings, but not the crude anger that powers common dark curses. We're talking about deeper emotions—grief, betrayal, despair."

Harry nodded, recalling the fragmented knowledge gleaned from Voldemort's memories. Under Arcturus's methodical instruction, those scattered pieces were finally beginning to make sense.

"The Midnight Spear," Arcturus demonstrated, his wand moving in a complex pattern. A javelin of pure darkness materialized, crackling with purple energy. "It draws power from loss and regret. The deeper the emotion, the stronger the spell."

Harry's first attempt produced only wisps of shadow. He couldn't generate enough intense emotion to get the spell right. Even thinking about his time with the Dursleys wasn't enough. Determined, he improvised, imagining scenarios in his mind that evoked stronger emotions. After a few more tries, he successfully created a solid spear that shattered their practice dummy.

"Good," Arcturus nodded. "But be careful. These emotions can poison your mind if you dwell on them too long. That's why a proper meditation session afterward is essential."

By the end of the day, Harry felt both exhausted and exhilarated. He had made significant progress, but the weight of the emotions he had tapped into lingered, reminding him of the fine line he walked.

The next morning brought another branch of dark magic. "Today, we'll delve into soul magic," Arcturus announced. "Not the crude horcruxes Voldemort favored, but subtler arts—spells to sense life force, detect if anyone is nearby, understand the connections between souls, and protect one's own soul from external influence."

"Soul magic is perhaps the most dangerous," Arcturus warned. "Not because of its immediate effects, but because mistakes here can damage you in ways that never heal."

They practiced several spells, and Harry found himself excelling in this area. His strong will, bolstered by his rebirth and the fragments of Voldemort's horcruxes he had absorbed, allowed him to grasp soul magic more easily than other types of dark magic. This was the only day he genuinely enjoyed his lessons, feeling a sense of accomplishment as he mastered each spell.

The following day focused on curse magic. "Now we'll study curse magic—not the simple hexes taught at school, but true curses that affect the very essence of their targets," Arcturus explained, gesturing to a new dummy that Mira had brought in. "The Withering Curse. Unlike the Killing Curse, which simply severs the soul from the body, this curse breaks down both flesh and spirit simultaneously. It's extremely painful, though slower than Avada Kedavra. A difficult spell that not many wizards can cast. Be sure to dodge this spell; it cannot be defended against by a shield charm."

Harry recognized this from Voldemort's memories—the Dark Lord had used it rarely, preferring the dramatic flash of the Killing Curse. The wand movement was complex: a triple spiral followed by a sharp downward slash. His first attempt produced only a faint grey mist that made the dummy's surface fade slightly.

"You're hesitating," Arcturus observed. "Dark magic requires conviction. You must mean it, must want to cause that destruction. Not out of hatred necessarily, but out of absolute certainty in your action."

Harry tried again, this time imagining using the spell to protect those he cared about. The curse struck true, the dummy crumbling to ash in seconds.

"Better," Arcturus approved. "Now for something more subtle—the Mind Maelstrom curse. It traps the victim in their worst memories, similar to a Dementor's effect but more targeted."

This spell proved particularly challenging. It required the caster to draw upon their own dark memories while maintaining enough mental distance to avoid being caught in the effect themselves.

"This is why proper Occlumency is essential for dark magic," Arcturus explained as Harry struggled. "You must be able to access these emotions while keeping your core self separate from them."

After a draining series of practice sessions, Arcturus called for a break. Mira appeared with revitalizing potions and light refreshments.

"Remember," Arcturus said as they rested, "dark magic leaves traces on the caster. That's why we perform the cleansing rituals daily. Miss even one day, and the residue begins to accumulate, affecting your thoughts, your magic, even your physical health."

Harry nodded, already feeling the effects—a heaviness in his chest, a slight darkening of his thoughts despite the precautions. "How do you avoid becoming addicted to it? I've seen in my research that many dark wizards seem unable to stop."

"The key is balance," Arcturus explained. "Light magic, dark magic—they're tools, nothing more. The moment you start favoring one exclusively, you lose perspective. That's why we'll also study advanced light magic—not the simplified versions taught at Hogwarts, but the ancient arts of healing, protection, and purification."

The following days were spent studying the purest forms of light magic, creating the necessary balance to offset their darker work. Harry found this combination challenging but essential, understanding that true mastery lay not in power alone but in maintaining equilibrium.

As the training progressed, he learned spells requiring sacrifice, rituals touching upon soul magic, and curses feeding on negative emotions. None except soul magic came easily to him—the dark arts felt wrong, twisted. But he persevered, knowing the importance of understanding both the spells and their counters.

Each evening after training, Harry spent an hour in meditation, cleansing his mind of the day's darkness. The fragments of Voldemort's knowledge helped him grasp the concepts quickly, though the practical application remained challenging.

Arcturus ensured that Harry was introduced to every kind of dark magic before delving deeper into any particular branch. They moved on to soul magic one day, curses the next, and emotion-based spells after that. Each session was exhausting but necessary, equipping Harry with the knowledge and skills he needed to confront the looming threat of Voldemort and any other dark wizards in the future.

Despite the grueling training, Harry found moments of enjoyment, especially when he excelled in areas where his innate abilities shone through. His strong will and the residual influence of Voldemort's dark magic allowed him to master certain spells with ease, even if he personally found them unsettling.

By the end of the ten days, Harry had developed a rudimentary but solid foundation in various dark magics. He understood the importance of control, the necessity of balance, and the dangers that came with wielding such powerful forces. However, through the training, he realized how fortunate he had been during his battle with Voldemort at the resurrection. Thankfully, he hadn't given Voldemort any opportunity to use spells; otherwise, if any of these had hit him, he might have died.

Now, he felt more prepared to face whatever challenges lay ahead. He was ready to confront any dark lord. Although he might not use much dark magic and would focus more on his lightning magic, some of the dark spells gave him ideas. He was excited to experiment with them to make himself even more unbeatable.