Long before she became a name whispered among the most powerful beings across the universe, Guest had been nothing more than an ordinary little girl. Her childhood came to an abrupt end when HYDRA took her and subjected her to a series of classified experiments. The organization had become increasingly obsessed with the power of the Tesseract, hoping to discover a way to transfer its extraordinary energy into a human subject. Guest became part of that experiment. But the results were far beyond anything HYDRA had anticipated. During one of the experiments, the Tesseract unleashed an enormous surge of energy. Space itself seemed to fracture, and Guest disappeared from the laboratory, transported far beyond the boundaries of her own universe.

She didn't return home.

Instead, she found herself traveling between different worlds and dimensions, each one revealing something entirely unfamiliar. Over the years, she encountered ancient forms of magic, powerful sorcerers, and civilizations that understood forces Earth had barely begun to discover. Guest learned. She studied magic, mastered abilities that once seemed impossible, and gradually became extraordinarily powerful. Her connection to the energy of the Tesseract had given her access to something much greater than HYDRA had ever intended. Eventually, after years of absence, she returned to her original universe. But the girl who had disappeared was gone. Guest had become a sorceress of immense power, and her return brought consequences that quickly attracted the attention of the Avengers. Her actions, however, placed her in direct opposition to them. To the world, she was now considered a dangerous threat. To James Buchanan Barnes, she was someone from a much older chapter of his life. Their paths had crossed during the years when Bucky was still the Winter Soldier. Despite his conditioning and the circumstances surrounding their encounters, the two had developed a certain affection for each other. Guest had liked him, although her feelings had never reached the depth of what Bucky might have felt. Now, their lives had taken completely different directions. Bucky had escaped HYDRA's control and found a place among the Avengers. Guest, meanwhile, had returned as a powerful sorceress whose abilities were largely unknown. And for the first time, Bucky was preparing for a mission in which the target was someone he had once known personally.

Inside Avengers Tower, the Avengers gathered in the operations room, preparing for their upcoming mission. Tony, Steve, Natasha, Sam, and Bruce studied the classified files while Bucky stood beside the holographic display, dressed in his dark tactical suit.