Chapter 649: Powerful Enemy

The energy wave scattered outward, knocking the surrounding guards back. Li Na was also pushed back several steps by this immense power, her face turning deathly pale.

"You... who exactly are you?" Li Na looked at Li An in terror; she had never encountered such a powerful enemy.

Li An did not answer, merely smiling coldly, his eyes filled with a victor's pride. He charged forward again, black wings unfolding behind him like a dark eagle hunting, ready to deliver the final blow to Li Na.

However, at this critical moment, Li Na suddenly vanished. Li An was stunned, then immediately scanned the surroundings warily. Just then, a silver light struck from behind, its speed astonishing.

Li An reacted with extreme speed, shifting his body aside and narrowly dodging the attack. He turned his head and saw that Li Na had appeared behind him at some point, the long sword in her hand shimmering with cold light.

"Do you think you have won? It is still far from over!" Li Na sneered and launched another attack against Li An.

This time, she held nothing back; every strike contained enough power to be fatal. Li An dared not be careless either, responding to Li Na's assault with all his might. The two once again plunged into fierce combat.

Guo Yao, watching from the side, felt extreme anxiety. She knew she could no longer sit idly by and must provide support to Li An as soon as possible.

She took a deep breath, her hands quickly forming seals while she chanted words. As her incantation sounded, the surrounding air began to distort, as if controlled by some mysterious power.

"Freeze!" Guo Yao shouted loudly. A pink light shot from her hand, instantly freezing Li Na in place.

Seizing the opportunity, Li An launched a counterattack. Black energy waves surged toward Li Na like a violent storm. Although Li Na struggled fiercely, under Guo Yao's binding and Li An's fierce assault, she finally succumbed.

"Pfft!" A soft sound rang out. Li Na's sword was knocked away by a single strike from Li An. She herself suffered heavy blows, spat blood, and collapsed to the ground.

The guards of the Sky City, seeing this, all showed expressions of terror. They had never encountered such powerful enemies, nor did they expect Captain Li Na to be defeated by Li An and Guo Yao.

"Retreat!" one guard shouted, leading the others to withdraw quickly.

Li An and Guo Yao exchanged a smile; they knew they had finally succeeded in breaking through the first line of defense of the Sky City.

The two continued deeper into the Sky City, moving along the winding corridors. Various mysterious patterns and runes were carved on the surrounding walls, emitting a faint glow that made the entire castle appear even more enigmatic.

"Li An, where do you think the Ancient Key is hidden?" Guo Yao asked softly, her voice carrying a hint of tension and anticipation.

Li An shook his head. "I do not know either, but since we have come here, we must find it."

The two continued forward, occasionally encountering patrolling guards. But with their previous experience, they quickly resolved these troubles and continued advancing toward the castle's depths.

Just as they were about to reach the castle's core area, a massive crisis suddenly descended. A black beam shot down from the sky, instantly enveloping the entire castle within it.

"What is this?" Li An was terrified; he had never seen such a terrifying power.