In the quiet, peaceful weeks that followed the Fatui's great withdrawal, a new, and even more surprising, discovery was made. The profound, world-altering changes in Inazuma were not the only shifts that had occurred; a fundamental change had happened within Ren himself.
He had resumed his Cryo training, this time in a secluded, beautiful training ground within the expansive gardens of the Tenshaku, often under the watchful, and now much calmer, eye of Ganyu. He was practicing his shields, the familiar, cool, and still, energy flowing from him with an easy, practiced grace.
He went to erect a particularly large, complex dome, and as he focused his will, not only did the familiar, turquoise light of Cryo erupt from him, but it was accompanied by a sudden, sharp, and utterly unexpected, crackle of brilliant, violet energy. A web of pure, harmless, and beautiful, lightning arced across the surface of his ice shield before dissipating.
He stared, completely, utterly, and profoundly, shocked.
The news, of course, reached Ei almost immediately. She found him in the garden, looking at his own hands with a mixture of wonder, confusion, and a little bit of fear.
She approached him, a look of deep, profound, and almost sorrowful, understanding on her beautiful face. She gently took his hand and closed her eyes, her divine senses reaching out, not to his body, but to the very essence of the new, strange power that now resided within him.
"It is as I suspected," she said, her voice a soft, wistful murmur. "When you took the Gnosis, when its energy flowed through you… a part of it remained. It has bonded with you." She opened her eyes, and they were full of a deep, ancient, and very personal, memory. "The nature of this Electro… it is not like mine. Mine is the lightning of judgment, of divine, unyielding law. This… this is softer. Warmer. It feels… like Makoto's."
The Gnosis, the heart of her beloved sister, had left its final, beautiful, and permanent, echo within the soul of the boy who had rescued it.
And so began a new, even more surreal, phase of Ren's life in Inazuma. Just as Ganyu had been his mentor in the art of Cryo, Raiden Ei, the Electro Archon herself, became his personal tutor in the art of thunder.
Their training sessions were a strange, beautiful, and utterly unique, spectacle. Ren, true to his nature, had no interest in using his newfound Electro abilities for attack. His goal was not to wield the lightning as a weapon, but as a tool for movement, for evasion, for freedom.
Ei, understanding his gentle, protective heart, tailored her lessons accordingly. She taught him how to dissolve his own form into a momentary burst of pure, harmless lightning, allowing him to teleport short distances with a sharp, exhilarating crack. She taught him how to use the Electro energy to manipulate the magnetic fields around him, allowing him to not just hover, but to truly, properly, fly, his body wreathed in a soft, crackling, violet aura.
Their spars were a beautiful, impossible dance. Ei, in her divine, majestic form, would move with a speed that was a blur to the naked eye, her naginata a storm of graceful, powerful strikes. And Ren, a small, laughing, and impossibly agile, blur of blue and violet, would never meet her attacks head-on. He would teleport, he would fly, he would phase through her strikes, a living, joyful bolt of lightning. He would use his Cryo shields to block and his Electro speed to dodge, occasionally managing to land a playful, harmless burst of frost on her arm, a laughing attempt to "immobilize" a god who was, of course, far too fast and far too strong to ever be truly caught.
Their connection deepened beyond that of a teacher and a student. They became friends. Ren, with his new, divine mandate as the "Eyes of the Shogun," would take Ei on walks throughout the new, healing Inazuma. He would show her the grateful, happy faces of the people whose Visions had been returned, the bustling, prosperous markets, the children laughing in the streets. He was showing her, in a thousand small, beautiful ways, the nation her sister had dreamed of, the nation that she herself was now helping to build.
The people of Inazuma, seeing their reclusive, terrifying god now walking openly, peacefully, and with a soft, gentle smile on her face, alongside the small, beloved, and now doubly-powerful, Liyuean hero, came to their own, logical, and heartwarming, conclusion.
He was no longer just "Liyue's Azure Savior." He now had a new, Inazuman title, a name whispered with a mixture of reverence, of awe, and of deep, profound affection. They called him the "Prince of Thunder."
Yae Miko, of course, found this entire development to be the most entertaining thing to have happened in centuries.
"My, my," she teased them one day, as she found them sharing dango in the city. "The people are already classifying our dear Ren as your successor, Ei. The Prince, to their Shogun. You must be careful. If word of this reaches Liyue, Morax might get jealous and decide to bring a few of his stone asteroids this way, for you stealing his own, unofficial, successor."
Ei, for the first time in five hundred years, did not ignore Miko's teasing. She simply looked at the small, laughing boy at her side, the boy who had broken through her eternal stillness and had brought not just change, but a profound, unexpected, and very, very, welcome, joy, into her life. And a small, genuine, and undeniably, happy, smile graced the lips of the god of Eternity.