Doctor Sato, with a gaze that mixed compassion and determination, guided Ren through the chaos that still reigned in Maruyama Park. Dodging police officers, paramedics, and curious onlookers, they reached an unmarked black van parked discreetly on a side street."This is my mobile lab," explained the doctor as she opened the back doors, revealing an interior filled with screens, wires, and strange devices blinking with colorful lights. "Here we can better analyze the situation and prepare your training."Ren, still shocked by Aiko's disappearance and overwhelmed by the technological display before his eyes, allowed himself to be guided by the doctor. Sato sat him in front of a screen where images of the vortex, captured by the park's security cameras, were playing."As I explained, that vortex is a dimensional portal that connects our world with another. A world inhabited by yokai," said Sato, pointing at the screen. "Supernatural creatures with powers that defy our understanding.""And Aiko is there? With the yokai?" asked Ren with a trembling voice, imagining his sister surrounded by monsters."It's the most likely scenario," replied Sato gravely. "Fortunately, the dimensional tracker picked up her energy just before the portal closed. We know she's alive, and we have a vague idea of her location."A holographic map projected onto the screen, showing an archipelago of floating islands in a purple sky. A red dot blinked on one of the islands."That's the yokai world," explained Sato. "And that red dot is Aiko's last known location."Ren contemplated the map with a mixture of awe and terror. It looked like a place out of a dream, or rather, a nightmare."But... how am I going to get there? And even if I do, how am I going to face those... yokai?" asked Ren, feeling hope fade."That's what the training is for," said Sato firmly. "We can't allow you to venture into that world unprepared. Yokai can be dangerous, and you'll need to learn to defend yourself."Sato activated another device, a kind of helmet with electrodes that she placed on Ren's head."This will help you develop your latent abilities," she explained. "We all have hidden potential, a connection to the spiritual energy that surrounds us. This device will help you awaken that potential, control your own energy, and use it to defend yourself."Ren felt like a guinea pig, but the desperation to rescue Aiko pushed him forward. He closed his eyes as the helmet activated, and prepared for whatever was to come.The training was intense and exhausting. For days, Ren underwent sessions that challenged his physical and mental limits. He learned to channel his energy, to sense the presence of yokai, to defend himself against invisible attacks, and to use his own energy to create protective shields. Sato guided him patiently, correcting his mistakes, encouraging him to overcome his fears.Gradually, Ren began to feel a change within himself. An unknown force was awakening in him, a connection to something greater than himself. His senses sharpened, his movements became more fluid, and an unusual confidence grew in his heart.Finally, the day of the final test arrived. Sato took him to a simulation chamber, a circular room with walls that projected holographic images. Ren found himself in a dark forest, surrounded by grotesque creatures that attacked him with sharp claws and menacing fangs.Ren, remembering Sato's teachings, focused on his energy, channeling it into his hands. He created a protective shield that protected him from the attacks, and then counterattacked with bursts of energy that made the creatures recoil.The battle was fierce, but Ren, with a determination he had never known before, managed to defeat all the yokai. When the simulation ended, Ren was panting, but with a sense of triumph flooding him."You did it, Ren," said Sato with a smile of approval. "You're ready."Ren looked at her with gratitude. He knew the path ahead was dangerous, but now he felt prepared to face it. For Aiko, he would face anything."Thank you, Doctor Sato," said Ren with determination. "I'm ready to rescue my sister."Sato nodded, and with a look of complicity, activated the dimensional portal. A new vortex opened before them, this time in the mobile lab. Destiny awaited on the other side.