The public dismantling of the Ministry's narrative in the Gryffindor common room had a profound effect. While the rest of the school remained steeped in Ministry-fed doubt, Gryffindor House, for the most part, solidified behind Harry. Seamus Finnigan, deeply humbled, offered Harry a quiet, sincere apology. The atmosphere in the tower became one of defiant unity, a small island of truth in a sea of denial.
This newfound peace, however, did little to soothe the turmoil in Harry's mind. His Occlumency lessons with Snape continued their brutal, incremental progress, but the visions were getting stronger, more vivid. One night, just before the Christmas holidays, he was jolted from a restless sleep by a horrifyingly real dream. He wasn't himself; he was a great serpent, slithering through a dark, sterile corridor. He saw a man—Arthur Weasley—and he felt a surge of cold, venomous fury as he struck, his fangs sinking into the man's flesh.
He awoke with a scream, his scar burning, the taste of blood in his mouth. He didn't hesitate. He immediately sought out Professor McGonagall, who took him straight to Dumbledore's office.
When Harry recounted his vision, Dumbledore's expression became grave. He immediately sent his phoenix Patronus to the Ministry. The news came back within the hour: Arthur Weasley had been found bleeding heavily from a venomous snakebite in the Department of Mysteries. He had been rushed to St. Mungo's, but thanks to Harry's timely warning, he had been found before he could bleed to death. He would make a full recovery.
The incident was another stark, undeniable piece of evidence. Harry's connection to Voldemort was real, and it could, paradoxically, be used as a weapon against him.
It was this event, combined with the utter uselessness of Professor Stump's Defence classes, that cemented an idea that had been brewing in Hermione's mind.
"He's out there," she said, her voice low and serious as she sat with Harry, Ron, and Ariana in the common room. "Voldemort. He's attacking people. And we are being taught nothing. We have to do something."
"What can we do?" Ron asked glumly. "Stump just has us reading Slinkhard's book over and over again."
"We can teach ourselves," Hermione said, her eyes alight with a familiar, fierce intelligence. "No, not just ourselves. We can teach everyone who wants to learn. We can start a defence group. And Harry," she looked at him, her expression full of conviction, "you have to be the one to teach us."
Harry stared at her. "Me? Teach? I'm not a teacher."
"You're one of the only two in our year who can cast a corporeal Patronus," she argued. "You've fought Dementors and Voldemort himself multiple times. You have more practical experience than anyone in this castle, including most of the professors. You have to do it."
The idea was daunting, but it also sparked something in Harry. It was a chance to fight back, to be proactive instead of just a target. "Okay," he said slowly. "I'll do it."
The first meeting of what Ginny Weasley cheekily christened "Dumbledore's Army"—a name they adopted as an act of open defiance against the Ministry—was not held in secret. With Umbridge gone, there were no Educational Decrees forbidding student groups. Ariana, using her now considerable influence with the Heads of House, secured them a large, unused classroom on the third floor for their "private study group." There was no need for the Room of Requirement, no need for passwords or secrecy. Their rebellion was out in the open.
The turnout was impressive. A score of students from Gryffindor, Hufflepuff, and Ravenclaw showed up, including Neville, Luna Lovegood, Cho Chang, and the Weasley twins. They were the ones who had chosen to believe Harry, the ones who were willing to defy the Ministry's narrative.
Harry, though nervous, was a natural teacher. He started with the basics, teaching them a proper Disarming Charm, his instructions clear, practical, and based on his own hard-won experience.
After the first successful meeting, Hermione, flushed with excitement, approached Ariana. "It was brilliant, Ari! You should join us! You could teach the advanced students! Imagine what they could learn from you!"
Ariana, who had been observing the proceedings from a chair in the corner of the room, looked up from her book, her expression calm and unreadable.
"What you are doing is a logical and necessary response to an educational deficit," she said, her voice holding a note of genuine approval. "Harry is a competent instructor of practical magic. You are providing a valuable service."
"So you'll help us teach?" Hermione pressed, her eyes shining.
"No," Ariana said simply.
Hermione's face fell. "But… why not? You're the best at Defence in the whole school! You could help so many people!"
Ariana closed her book. "Hermione," she said, her voice not unkind, but devoid of sentiment. "Let us analyze the composition of this group. It includes Neville, who has proven his loyalty. It includes Luna, whose perspective is unique. It includes you, Harry, and Ron. But it also includes Zacharias Smith, who openly questioned Harry's integrity. It includes Marietta Edgecombe, whose mother works for the Ministry and reports to Fudge, who herself has been slacking off during training sessions. And it includes at least a dozen others who, just last year, were wearing 'Potter Stinks' badges and openly calling Harry a liar in the corridors a few weeks ago."
She met Hermione's gaze, her own cool and clear. "They are not here because of a sudden, profound belief in Harry's righteousness. They are here because the idea of a secret club is exciting, not because they are afraid of the escaped Death Eaters, but because they want to learn powerful flashy spells. Their loyalty is to their own self-interest, not to our cause."
She stood up, her presence commanding a quiet authority. "I will not waste my time and energy teaching defensive magic to fair-weather friends and potential informants. My focus is on our core alliance. I will continue to train Harry, and you, and Daphne, in the Room of Requirement, with magic that is far beyond the scope of a simple Disarming Charm. But I have no interest in teaching a classroom full of students whose convictions are as shallow as a dinner plate."
Her logic was brutal, uncompromising, and, as always, unassailable. She applauded their effort. She supported their goal. But she refused to participate in what she viewed as a fundamentally flawed and insecure operation.
"You are building an army, Hermione," she concluded, her voice softening slightly. "And that is admirable. But I am training generals. The two are not the same."
With that, she turned and left the classroom, leaving Hermione to grapple with the difficult truth. Ariana's loyalty was a deep, powerful, and absolute thing. But it was a resource she would not squander on those who had not earned it. Her war was being fought on a different, more exclusive front.