After returning to the safe house, Su Yao and her family, without even taking a break, began organizing the supplies they had brought back. High-tech equipment was taken out one by one, its functions carefully checked, and then categorized and stored. Medical supplies were properly placed in a dedicated storage area to ensure they could be quickly found when needed.

However, before they could fully settle in, the system issued a new alert: "Abnormal energy fluctuations around the safe house; an unknown force is approaching." Su Yao frowned. She knew that in this apocalypse, there was never a moment of true peace.

She quickly reached the lookout point of the safe house and saw several black dots appearing on the snow in the distance. As they drew closer, she could gradually make out that they were a group of strangers dressed in heavy protective suits and well-equipped. Their steps were synchronized, and their movements revealed a well-trained demeanor; they were clearly not ordinary survivors.

Su Yao whispered to her family to prepare for defense, then went to the entrance of the safe house. When the group arrived not far from the safe house, the burly man at the head of the group shouted loudly, "We mean no harm. We just heard that some extraordinary people here have obtained a large amount of valuable resources. We are short of resources and hope to make some exchanges."

Su Yao looked at them warily and replied, "We barely escaped with our lives to get these supplies, and we don't even have enough for ourselves, so we have nothing to exchange." Upon hearing this, the burly man's expression changed slightly, and a barely perceptible glint of ferocity flashed in his eyes.

Just then, Su Yao sensed an unusual energy fluctuation emanating from the group, and she inwardly cried out in alarm. Suddenly, several of them pulled out special energy emission devices from their backs and launched an attack on the safe house. Su Yao quickly used her spatial abilities to create a barrier in front of the safe house, blocking the attack.

"You're courting death!" Su Yao roared, unleashing her wind blade ability to attack the enemies. Although they were protected by energy shields, these shields began to waver under Su Yao's powerful attacks. A fierce battle ensued.

During the battle, Su Yao discovered that these people's weapons and equipment seemed to have a certain adaptability to energy magnetic fields, and their power was much stronger than that of the enemies they had encountered before. Moreover, they cooperated very well, with some people specifically responsible for attacking, some for defending, and others searching for weaknesses in the safe house's defenses.

While fighting, Su Yao pondered a strategy. She decided to first find the controller of the enemy's energy core; only by disrupting their command could she have a chance of victory. She used her spatial abilities to stealthily move through the enemy ranks, searching for her target.

Finally, she spotted someone at the rear of the group, constantly manipulating equipment and directing the battle. Su Yao gathered all her supernatural abilities and launched a powerful fusion attack. A dazzling light shot towards the target; the opponent sensed the danger and tried to dodge, but it was too late. The energy core controller was struck and instantly lost control of the group.

The enemy's attack became chaotic and disorganized. Su Yao seized the opportunity and led her family in a counterattack. Utilizing the terrain and defensive structures around the safe house, they engaged in a fierce battle with the enemy. During the fight, Su Yao discovered another weakness in the enemy: their protective suits experienced performance degradation under high temperatures.

Su Yao then activated her fire-based abilities, unleashing a concentrated attack on the enemy. Flames burned on the snow, and the enemy's protective suits began to melt and break under the intense heat. Their movements became sluggish, and their combat effectiveness was greatly reduced.

After a fierce battle, Su Yao and her family successfully repelled the unknown forces. However, the safe house was damaged to some extent and needed to be repaired as soon as possible. While repairing the safe house, Su Yao began to think about how to strengthen its defenses to cope with potential future dangers.

Using materials brought back from military bases and secret warehouses, she installed more concealed protective devices and energy shield generators around the safe house. She also upgraded the safe house's alarm system, making it more accurate and effective at detecting surrounding dangers.

After several busy days, the safe house's defenses were greatly improved. However, the system sent another message: "Research data clues that may be related to the cause of the apocalypse have been discovered in the ruins of a city far from the safe house." Su Yao knew that this could be an opportunity to change their fate, and she decided to set off again on a new journey.