After Su Yao and her family successfully returned to the Alliance base, they immediately organized a research team to study the seven-colored crystal core. However, the secrets of this crystal core were too profound, and progress was extremely slow. At the same time, zombie activity around the Alliance base became increasingly frequent, as if a mysterious force was secretly controlling it.

Su Yao decided to venture out again, sensing that something was amiss. This time, they arrived at an industrial city shrouded in dark mist. The city reeked of pungent chemicals, and zombies appeared and disappeared in the mist, emitting chilling growls.

As soon as Su Yao stepped into the city, she felt a chill creep over her. She cautiously released her spiritual energy to investigate, only to find it was swallowed up by an unknown force, like a stone sinking into the sea. "Everyone be careful, something's wrong here," Su Yao whispered to her parents.

As soon as she finished speaking, a horde of zombies pounced from all directions like ghosts. Su Yao quickly used her ice-based abilities, but the zombies seemed unfazed by the cold, breaking through the ice shards and continuing their attack. Seeing this, her father immediately used his earth-based abilities to build a thick earthen wall in front of them. Her mother nervously watched their surroundings, ready to provide support with her healing abilities at any moment.

Just as the battle reached a stalemate, Su Yao noticed that the zombies' eyes were flashing with an eerie red light. A thought struck her, and she activated her spacetime ability, briefly distorting space and causing the zombies to become disoriented. Taking advantage of the situation, she forcibly invaded the consciousness of one of the zombies with her mental abilities, only to discover that these zombies were controlled by a mysterious crystal core energy.

"It seems we need to find the source of the energy fluctuations to solve this problem," Su Yao said. So, they fought off the zombies while searching for the source of the energy fluctuations.

In an abandoned factory in the city center, Su Yao finally sensed a strong fluctuation of crystal core energy. The three of them carefully sneaked into the factory and saw a huge device inside. At the center of the device was a crystal core emitting a dark light, and it was connected to countless pipes that were continuously transmitting energy to the surrounding areas.

"It's this thing that's causing trouble!" Su Yao's eyes turned cold. Just as she was about to step forward to destroy the device, a group of mysterious people dressed in black robes suddenly appeared from all around.

"Do you think you can easily ruin our plans?" a mysterious man sneered.

Su Yao was fearless: "Who exactly are you people? Why are you controlling zombies to attack the Alliance?"

The mysterious figure didn't answer, but instead launched an attack. A black energy beam shot from the black-robed man's hand, and Su Yao and her family hurriedly dodged. Su Yao unleashed a Space-Time Flame Blast, blasting it towards the mysterious group. The mysterious figures scattered; their abilities seemed to be related to the Dark Crystal Core, allowing them to move freely in the darkness, making it difficult for Su Yao's attacks to hit them.

The father used his earth-based powers to alter the factory's terrain, creating traps in an attempt to ensnare the mysterious figures. The mother, meanwhile, empowered Su Yao with healing energy, enhancing her sustained combat ability. During the battle, Su Yao discovered that these mysterious figures were not to be underestimated, and that they seemed to be deliberately stalling for time.

"We can't let them succeed; we must destroy the crystal core as soon as possible!" Su Yao thought anxiously. She activated her spatial ability, attempting to teleport directly to the crystal core, but a powerful force repelled her.

At this moment, the mysterious figure intensified his attacks, and zombies continued to pour into the factory. Su Yao's family was caught in a fierce battle. Just at the critical moment, while dodging the attacks, Su Yao's father accidentally triggered an advancement in his earth-based abilities. A layer of golden light surged around his body, and his earth-based abilities became even more powerful, capable of instantly turning large areas of the ground into quicksand, trapping enemies and zombies.

With the help of her father's enhanced abilities, Su Yao successfully escaped the mysterious man's entanglement and rushed towards the crystal core. Ignoring the energy surge surrounding the crystal core, she forcefully suppressed its power with her mental abilities and then stored it in her system space. Deprived of the crystal core's energy, the zombies instantly stopped attacking and collapsed. Seeing the situation was dire, the mysterious man tried to escape.

"Trying to leave? Not so easy!" Su Yao used her spacetime ability to seal off the surrounding space, trapping the mysterious man inside. After a fierce battle, they finally subdued all the mysterious men.

Su Yao learned from the mysterious person that they were an organization called the "Shadow Cult," who attempted to control zombies using crystal cores and rule the entire post-apocalyptic world. This dark crystal core was just one part of their plan.

Carrying this astonishing news and the dark crystal core, Su Yao and her family returned to the Alliance base. They knew that the Alliance was about to face an unprecedented crisis. The Shadow Order would not let things rest, and the secrets hidden behind the crystal core far exceeded their imagination. In the days to come, Su Yao must lead the Alliance to quickly increase its strength and unravel all the secrets of the crystal core in order to protect humanity's last glimmer of hope amidst the dark tides of this apocalypse and face an unknown and challenging path of destiny.