Gu Jin narrowed her eyes. "Either they didn't reach this place… or they reached it and never came back."
Mimi looked nervous now. "So… you think it's a trap?"
Gu Jin nodded. "It might be. A very clever one. Something we haven't seen yet."
Mimi looked back at the altar, then grabbed a nearby stone. "I'll check."
Before Gu Jin could stop her, Mimi tossed the stone toward the altar.
The moment the stone passed into a 200-meter range of the altar, something terrifying happened.
Not slowly. Not with a sound.
It disappeared all at once, swallowed by thick, dark fog that shot up from the ground like smoke.
The peaceful clearing transformed in the blink of an eye. The trees twisted, the sky darkened, and a sharp sound echoed through the air.
It was the sound of a blade slicing through something.
Gu Jin and Mimi both froze.
For a moment, their hearts pounded in their chests, but neither of them moved.
The fog thickened for a second… then slowly faded, as if it realized no one had walked into the trap.
As the fog vanished, the altar reappeared, sitting there like nothing had happened.
Mimi took a step back and whispered, "That was amazing… scary, but amazing. It reacted just to a small stone."
Gu Jin nodded slowly. "That's not just a normal trap. That's something built to sense life. It only acts when it thinks a living person is nearby."
Mimi shivered and looked at the altar.
"Maybe… maybe that's why the others failed. They reached here and thought the hard part was over. They let their guards down."
Gu Jin stared at the altar, her eyes still narrowed.
"Maybe," she said. "But I don't think that's all. There's something else here. Something… too perfect."
Mimi gave her a confused look. "What do you mean?"
Gu Jin didn't answer right away. She just stood there, thinking hard. Her instincts were telling her that everything so far, every trap, every beast, even the altar itself, was part of a bigger test.
But what exactly it was, she still didn't know.
"I don't know yet," Gu Jin finally said. "But we're missing something. Something very important."
Mimi nodded slowly. "Then… what do we do now?"
Gu Jin stared at the altar one more time.
Gu Jin stared at the altar one last time, her eyes sharp and thoughtful. Then, suddenly, she snapped her fingers.
A moment later, a figure appeared beside her.
It wore a long dark cloak, hiding most of its body. Its face was hard to see under the hood, but its greenish skin was clear in the faint light. The figure stood tall and still, almost like a statue.
Mimi's eyes widened. Her body tensed.
"That's not an undead," she said in a low voice. "That… that's a summoned soul. It feels different."
Gu Jin nodded with a small smile. "You're right. This is one of my skeleton warriors. I summoned him using necromancy."
Mimi blinked in surprise and stepped closer to the figure. "He feels so calm… like he's just waiting."
Gu Jin turned to her skeleton warrior and pointed toward the altar. "Go. Bring back the box."
The skeleton warrior didn't speak. He walked forward, each step slow and steady, moving across the clearing.
Mimi watched nervously. "Aren't you worried?" she whispered. "What if the trap activates again?"
Gu Jin kept her eyes on the altar. "No. I have a theory. If I'm right, then nothing will happen to him."
Mimi frowned. She still didn't feel sure, but she trusted Gu Jin, so she didn't ask anything more.
Together, they watched as the skeleton warrior reached the edge of the altar's circle.
One step… two steps… nothing happened.
He kept going, calm and smooth, until he stood right in front of the altar.
The box sat quietly on top of it.
The skeleton reached out, picked it up, and turned around.
Still, no fog. No darkness. No sound of blades.
He returned to Gu Jin without a single problem and placed the box in her hands.
Mimi's mouth fell open in surprise. "It didn't attack him at all. Is it because he is a soul?"
Gu Jin slowly shook her head. "Not exactly. It's because of his energy."
Mimi tilted her head. "What do you mean?"
Gu Jin held the box tightly and looked at the clearing around them. Then she looked back at Mimi.
"I've been thinking," she said. "All this fog, the soul energy, the red crystals… even the way the traps react. It all has one thing in common."
Mimi's eyes widened as she caught on. "Necromancy…"
Gu Jin nodded. "Yes. I believe this entire mountain is filled with necromancy-type energy. It's everywhere. In the ground, the air, the plants. It's mountain once belonged to a powerful necromancer."
She looked at the altar again.
"That necromancer might have been the first person to hold the key to the ancient temple. But he was chased or hunted, and he escaped to this mountain. Maybe he couldn't return. So he turned the mountain into a place only people like him could survive in."
Mimi frowned, her mind racing.
"But… there were plant traps, soul wraiths, even illusion loops. Wouldn't that mean people of all types died here?"
Gu Jin nodded again. "That's what led me to my second theory."
She looked serious now, her voice low and steady.
"What if the ancient temple belonged to necromancers from the beginning? The key always belonged to them. And when the enemies of the necromancers came after them, the last necromancer escaped with the key and built this mountain as a test. A place to hide the key and keep others out."
Mimi's eyes widened. "So all the traps… were never random?"
Gu Jin shook her head. "No. I think they were built to block anyone who wasn't a necromancer. To let only someone with necromancer energy or knowledge pass through safely."
Mimi frowned and looked at Gu Jin seriously.
"If you take the key now… won't the enemies who were chasing the necromancer long ago realize that you have necromancy powers too?"
Then she slowly nodded. "Yes. That's true."
Mimi looked worried, but Gu Jin gave a calm smile and added, "But I can hide it. Everyone already thinks I have an undead element, right? Even the whole country believes that."
Mimi blinked. "Right…"
"If China supports me and says I have the undead element, then others won't question it. They'll believe what they see on the surface," Gu Jin explained.
Mimi thought for a moment and then nodded. "That makes sense. You're really smart."
Gu Jin didn't reply. Instead, she turned her attention back to the box. Slowly, she lifted the lid.
But inside… it was empty.
"What?" Mimi gasped, peering into the box. "There's nothing inside?"
Gu Jin frowned too. She picked up the box and looked at it from different angles. "Strange…"
"Was it all a trap?" Mimi asked, her voice shaky.
Gu Jin didn't answer. Instead, she narrowed her eyes and placed her hand gently on the wooden surface of the box.
She let a tiny strand of necromancy energy flow into it.
At first, nothing happened.
Then suddenly, the box glowed.
A golden light spread across its surface, and lines of old, glowing symbols appeared. Right in the center, something began to shimmer.
A long, thin key, made of dark silver and wrapped in faint black mist, slowly became visible.
Mimi gasped, eyes wide. "It was invisible all along!"
Gu Jin chuckled lightly. "I was right. Whoever hid the key made it so that only a necromancer could find it."
She looked at the key and added, "Maybe it was that strange person we met when we first entered the mountain. The one who vanished before we could ask anything."
Mimi nodded slowly. "It could be. Maybe he was guarding the key."
Gu Jin closed the box gently and placed it in her space. "Either way, we have it now."
With that settled, they turned to leave the mountain.
But the path wasn't easy.
After walking for nearly half an hour, Gu Jin frowned.
Something felt wrong.
She pulled out her notebook and checked the map she had carefully drawn. But when she looked around, the marks she had made on trees and rocks were all gone.
Even the path seemed different.
"Wait…" Mimi said, looking around nervously. "Where are the signs we made? Didn't we pass this rock already?"
Gu Jin narrowed her eyes and scanned the area. "We did. But… something's wrong."
"An illusion?" Mimi asked quickly. "It has to be. Right?"
Gu Jin stood very still, feeling the energy in the air. She waited… but there was no ripple, no twist in her senses. Everything felt real.
"No," she said softly. "It's not an illusion. The ground, the trees, even the air… all of it feels solid. It's not fake."
Mimi bit her lip. "Then what's happening?"