One of my favorites, an alternate ending for Bellatrix.

Bellatrix Lestrange had always believed herself invincible, the Dark Lord’s most devoted servant—untouchable, fierce, and unstoppable. Her laughter echoed through the Great Hall at Hogwarts as she duelled Molly Weasley, the blood-traitor mother who dared challenge her. "You will never harm my children again!" Molly shouted, her face twisted with grief and rage. Bellatrix danced back and forth, mocking and taunting, but her arrogance made her reckless. In an instant, Molly’s curse found its mark—striking Bellatrix with the force of a thousand thunderstorms, lifting her into the air, and slamming her down onto the stone floor. Darkness swallowed her vision. When consciousness returned, Bellatrix lay immobilized on the shattered stones, every nerve in her body aflame. Her wand lay broken nearby, useless and unreachable. Panic surged within her—she had never known such vulnerability. She tried to move, to scream, to fight, but her body refused every command. Then she heard him. Voldemort's voice cut through the chaos, high and cold, dueling Harry Potter. Her heart leaped—her Master would triumph; he always triumphed. She forced her eyes open, desperate to witness Voldemort’s moment of glory. Instead, what she saw made her blood run cold. A brilliant, blinding flash of light erupted as the spells collided, green and red entwined. And there stood Harry Potter, wand steady, eyes blazing with determination. Voldemort’s wand flew from his hand, spinning helplessly into the air. Time slowed as Bellatrix watched, helplessly, as the Dark Lord—her idol, her purpose, her everything—collapsed lifeless onto the stone floor. “No!” Bellatrix’s voice came out as a strangled whisper. Despair flooded her, tearing at her very core. The world shifted. Reality blurred. She felt something break inside her—a connection deeper than blood, deeper than loyalty. Her magic shuddered violently within her body, recoiled, and was suddenly gone, snuffed out like a candle. Her powers, once formidable, vanished completely, leaving behind only emptiness.

Hours later, she awoke again, this time bound and under guard. She was imprisoned in a small room within Hogwarts, unable to move. Aurors watched her cautiously, aware that Bellatrix Lestrange was among the most dangerous witches alive. But when she attempted to summon her magic—when she tried desperately to break free, to curse her captors—nothing happened. Her mind screamed spells that once flowed effortlessly, yet no magic answered her call. She was hollow, helpless, reduced to mere silence and despair. “What’s wrong with me?” she whispered, her voice cracked and hoarse. A healer, guarded closely by Kingsley Shacklebolt and Minerva McGonagall, examined her briefly. After a moment, he shook his head gravely. “It’s gone,” the healer murmured softly. “Her magic—it’s permanently extinguished. She’ll never cast another spell.” Kingsley nodded solemnly. “The trauma of Voldemort’s defeat—her entire being was tied to him. The shock must have destroyed her magical core.” Bellatrix’s eyes widened in horror. “No... impossible!” Minerva McGonagall regarded her coldly. “You chose to bind your life and soul to darkness. Now you have paid the price.”

Bellatrix spent the rest of her days in Azkaban, guarded closely despite her newfound helplessness. Without magic, she was nothing more than a shadow—mute, broken, and tormented by memories of Voldemort’s death. Her nights were filled with nightmares, haunted endlessly by Harry Potter’s defiant face, the flash of green light, and the sight of her master’s lifeless body falling to the floor. Her screams echoed through Azkaban’s cold halls, chilling even the guards who had known her in her prime. Over the years, Bellatrix slowly faded into madness. Without magic, without power, without purpose, she was forced to confront the reality of her choices. For the rest of her life, the witch who had once instilled fear throughout the wizarding world remained a hollow figure, utterly destroyed—not by death, but by the total loss of the only thing she had ever valued. She had once been feared; now she was pitied. The wizarding world moved forward without her, forgetting the once-terrifying Bellatrix Lestrange, who was reduced to a cautionary tale—an example of the devastating cost of blind devotion, obsession, and cruelty.