Su Yao and Ling Yu, carrying precious supplies and mysterious devices, continued their journey towards the mountain fortress. Snowflakes began to fall again, and the cold wind cut like a knife across their faces, but their steps were firm and powerful.

As they passed through a valley, Su Yao's system issued an alarm, alerting them to abnormal energy fluctuations nearby. They stopped and cautiously observed their surroundings. The valley was shrouded in thick fog, with extremely low visibility, and they could faintly hear low roars coming from within the fog.

"Something's not right here, let's be careful." Su Yao clenched her fist, her spatial abilities flickering in her palm. Ling Yu also prepared for battle, his ice-type abilities forming a faint ice crystal shield around him.

Suddenly, a colossal figure burst forth from the thick fog—a massive, truck-sized ice mammoth. Its tusks resembled enormous icicles, and its body was covered in thick, icy armor, causing the earth to tremble slightly with every step it took. The mammoth's eyes gleamed with ferocity as it charged towards Su Yao and Ling Yu.

Su Yao quickly used spatial teleportation to teleport Ling Yu to the side. The mammoth's massive body crashed into a nearby rock, shattering it instantly. "This behemoth is tough to deal with; we need to find a way to attack its vitals," Ling Yu shouted.

Su Yao activated the system scan and discovered areas of concentrated energy on the mammoth's head and abdomen, which might be its weak points. She shared this information with Ling Yu, and the two began to formulate a battle plan.

Ling Yu first used his ice-type ability to create a large number of ice spikes around the mammoth, attempting to restrict its movement. However, the mammoth stomped its foot forcefully, shattering the ice spikes. Taking advantage of this opportunity, Su Yao activated her wind blade ability, sending wind blades flying towards the mammoth's eyes like raindrops. Attacked, the mammoth roared angrily and swung its trunk at Su Yao.

Su Yao teleported away again, and Ling Yu seized the opportunity, conjuring a huge ice spear and shooting it towards the mammoth's belly. The ice spear struck the mammoth's belly, splashing up a spray of ice and snow, but only leaving a shallow mark on its icy armor.

The mammoth became even more ferocious, charging madly at Ling Yu. Ling Yu continuously used his ice wall to defend himself, but the ice wall shattered rapidly under the mammoth's powerful impact. Seeing the situation was dire, Su Yao teleported onto the mammoth's back and activated her spatial compression ability, attempting to attack the mammoth from the inside.

Sensing the threat on its back, the mammoth violently shook its body. Su Yao struggled to steady herself while simultaneously activating her fire ability. Flames erupted on the mammoth's back, melting part of its icy armor. The mammoth roared in pain, attempting to use its trunk to throw Su Yao off.

Taking advantage of the opportunity, Ling Yu once again condensed an ice spear. This time, he increased the power of the ice spear to its maximum and shot it towards the area on the mammoth's head where energy was concentrated. The ice spear collided with the mammoth's head, producing a deafening sound, and the mammoth was somewhat dazed by the blow.

Seizing the opportunity, Su Yao unleashed her strongest combined spatial and fire abilities, targeting the weak point in the mammoth's abdomen that had already melted. This time, the attack successfully pierced the mammoth's abdomen, and black blood flowed from the wound, dripping onto the snow and emitting wisps of blue smoke.

The mammoth crashed to the ground, kicking up a cloud of snow. Su Yao and Ling Yu, panting heavily, collected some usable supplies from the mammoth's carcass, such as its ivory and fur, which were of great value in the apocalypse.

Continuing on, they came to a frozen river. The ice on the river seemed solid, but the system warned of danger beneath. Su Yao used her spatial abilities to probe beneath the ice and discovered a group of crocodile-like ice crocodiles swimming on the ice. Their teeth were incredibly sharp, and if anyone stepped onto the ice, they would break through and attack.

After thinking for a moment, Ling Yu said, "We can lure them out and take them down one by one." Su Yao nodded in agreement. She took out a piece of meat she had found at the research station and used her spatial ability to send the meat to the center of the ice.

Soon, cracks began to appear on the ice, and an ice crocodile burst through the ice, lunging at the chunk of flesh. Ling Yu quickly used his ice-type ability to freeze the ice crocodile's body, while Su Yao unleashed a wind blade, severing the ice crocodile's neck.

But more Icefield Crocodiles were attracted, and they broke through the ice. Su Yao and Ling Yu stood back to back, engaging the Icefield Crocodiles in fierce combat. Su Yao continuously used spatial teleportation to dodge the Icefield Crocodiles' attacks, while simultaneously using her supernatural abilities to attack their eyes and abdomens. Ling Yu, on the other hand, used his ice-based supernatural abilities to create various ice weapons, engaging the Icefield Crocodiles in close combat.

During the fierce battle, Su Yao discovered that the Icefield Crocodiles would pause briefly before attacking, and she told Ling Yu about this discovery. The two cooperated even more seamlessly, and after a hard-fought battle, they finally eliminated all the Icefield Crocodiles.

After crossing the river, the mountain fortress came into view. The snow-covered fortress exuded a mysterious aura. Su Yao and Ling Yu knew that more challenges might lie ahead, but also the supplies they craved and a safe haven. They took a deep breath and headed towards the mountain fortress, preparing to embrace the unknown.