Genshin Impact.

Under the guidance of the old man, Lin Feng and Li Er overcame all obstacles along the way and gradually approached the truth behind the numerous obstacles. At this moment, they were standing in a desolate valley, surrounded by a silence that made people feel creepy.

"Brother Feng, I always feel that there is something indescribable weirdness here." Li'er tightly grasped the corner of Lin Feng's clothes, with a hint of fear in her eyes.

Lin Feng gently patted Li'er's hand and comforted her, "Don't be afraid, I'm here." He glanced around vigilantly, and the magic sword in his hand flashed a faint light.

At this moment, a thick fog suddenly surged in the valley, quickly enveloping the three of them. Seeing this, the old man waved his cane and a beam of light shot out, trying to disperse the thick fog, but the thick fog seemed to have life and kept swallowing up the light.

"There's something strange about this fog." The old man frowned, looking serious.

Lin Feng closed his eyes and carefully felt the surrounding atmosphere. Suddenly, he opened his eyes and rushed in one direction. Li'er and the old man followed closely behind him.

Deep in the fog, they found an ancient stone tablet, which was engraved with strange runes and exuded a mysterious atmosphere.

Lin Feng walked forward and carefully observed the runes on the stone tablet, trying to interpret their meaning. Just as he was concentrating, the runes suddenly flickered and turned into rays of light that shot into Lin Feng's mind.

A sharp pain came, and Lin Feng fell to the ground holding his head, rolling in pain. Li'er was anxious and wanted to help, but was stopped by the old man.

"Don't be impulsive, this may be the key to solving the puzzle." said the old man.

Li'er had no choice but to wait anxiously. After a while, Lin Feng slowly stood up, with a glimmer of understanding in his eyes.

"I understand. These runes are a kind of guidance." Lin Feng said, "They point to a place."

Led by Lin Feng, they passed through the thick fog and came to a cave. The entrance of the cave was filled with a strong aura that made people stay away.

Lin Feng took a deep breath and walked into the cave first. The cave was dark and damp, with strange lights flickering on the walls. They walked forward cautiously, and suddenly, a group of black shadows rushed over from all directions.

Lin Feng brandished his magic sword and started a fierce battle with the black shadows. Li Er also cast a spell to assist Lin Feng. With their joint efforts, the black shadows were gradually eliminated.

However, the danger was not over. Deep in the cave, they found a huge magic circle. In the center of the magic circle, there was a black crystal that exuded an evil aura.

"This is..." The old man's expression turned extremely ugly, "This is the place where the Demon Lord was sealed."

It turns out that a powerful demon lord once appeared on this continent, and he attempted to destroy the world. After a fierce battle, the ancestors of the Immortal Sect sealed the demon lord here. However, as time passed, the seal gradually loosened, and the demon lord's breath began to leak, causing various abnormalities on this continent.

"We must reinforce the seal again, otherwise once the Demon Lord is born, the consequences will be disastrous." said the old man.

Lin Feng, Li'er and the old man worked together to inject their own magic power into the magic circle. The magic circle began to flash with dazzling light, and the evil aura on the black crystal was gradually suppressed.

After some effort, the seal was finally reinforced. Just as they breathed a sigh of relief, the cave began to shake violently, and countless boulders fell from the top of the cave.

"Hurry up!" Lin Feng pulled Li'er up and rushed out of the cave. The old man followed closely behind.

The moment they escaped from the cave, it collapsed. They looked at the ruins in front of them, their hearts filled with emotion.

“Although the seal has been reinforced this time, the power of the Demon Lord is still eroding. We must find a way to completely eliminate him as soon as possible.” said the old man.

Lin Feng nodded. He knew that their immortal journey was still very long and there were countless challenges waiting for them ahead...