"It looks like five high-level Yan crystals are needed to activate it. It seems that the power of this giant cannon is far superior to that of the divine craftsman's cannon." Shen Luo's eyes fell on the circular groove at the tail end of the golden cannon barrel, and his eyes lit up with joy.
He had more than a dozen high-level Yan crystals in his hand, which was enough to activate it. It was a pity that there was a divine ban in the gray tower, so he could not use this giant cannon. Otherwise, he could let Che Qingtian taste its power.
Shen Luo sighed with regret and put away the golden cannon.
The situation was urgent now and he had no time to check the other Yanjia one by one. He immediately activated the Xiaoyao Mirror to collect all the Yanjia and weapons in the hall.
Che Qingtian might come to this place sooner or later, and he doesn't want to leave this batch of precious Yan armor to him.
The hall suddenly became empty, but there was a black iron box placed on the innermost stone platform, emitting a faint black light, which blocked the Xiaoyao Mirror from collecting it.
"Hey, what is this box?"
Shen Luo was a little surprised. He walked over and tried to pick up the box, but the box seemed to be cast on a stone platform, and the stone platform was also connected to the ground, so he couldn't lift it at all.
He thought to himself that it was strange, took two steps back, and swung out the Pure Yang Sword to chop it.
There was a loud bang of metal hitting stone, the sword flashed, and the iron box burst into flames, but it was surprisingly safe and sound.
Just as Shen Luo was about to lean over to take a closer look, the black light on the iron box suddenly fluctuated and quickly condensed into a book-like light curtain, flickering gently, as if waiting for something.
"Secret key restriction?" Shen Luo muttered to himself when he saw this.
He had heard about this kind of restriction from Huo Lingzi. It was usually used to guard secret rooms or treasures. It could only be opened by writing the correct secret key. The secret key could be a spell, text or picture. Forcing it to open would only cause the restriction to self-destruct and destroy the treasure guarded by the restriction.
Shen Luo thought about it for a moment, and golden light appeared on his fingers, writing the word "偃" on the light curtain of the scroll, but it disappeared quickly. Neither the light curtain nor the iron box responded at all, and it was obvious that the key was wrong.
He thought about it and wrote the three words "Tianyan Palace" on the light curtain again, but it was still wrong.
Shen Luo frowned and entered all possible keys, but there was still no response.
"It seems that the owner of this iron box has set a special key. I'm new here and I'm afraid I won't be able to open it. Let's just forget it." He was not greedy. He turned around and was about to leave when an idea suddenly popped into his mind.
"Maybe..." He turned around and drew a complex pattern on the light curtain of the scroll, which was exactly the last identification pattern on the map scroll.
The pattern had just been completed when the light curtain of the scroll suddenly fluctuated violently, then shrank back into the black iron box in a flash, and the other black lights around the iron box also retracted.
The lid made a "click" sound and opened automatically.
Shen Luo suppressed his excitement, looked inside the box, and raised his eyebrows.
Inside the box was a half-foot long black iron rod with many patterns and bumps carved on it, which looked like another key.
"Key? What does it open?" Shen Luo took out the item.
At this moment, a green wall next to the stone table suddenly shook, and countless blue-gray fragments fell off. After a few breaths, a tightly closed bronze door appeared on the wall. It was twenty or thirty feet high and looked very spectacular.