In the library, the Head Array Master led William to a row of books. "These are all the forbidden Arrays we have records of. Some of the information is incomplete, but it may still be of use to you."
William felt now would be a good time to ask, "What makes an Array forbidden?"
"The Royal Family of Azures declared certain topics as forbidden based on their qualities. They've placed a ban on anything which is intended to kill humans, enslave people, or anything powerful enough to destroy the world. The Techniques are forbidden for use, but there is no law against learning about Forbidden Arrays like this one." the Head Array Master placed his hand on a specific book with an orange cover.
He pulled it off the shelf and handed it to William. "The basics of Forbidden Arrays are here. All who delve into the secrets of Forbidden Arrays are recommended to read this first."
William took the book and opened it to the first page. Unlike in Thin Creek Village, this book had a table of contents. He flipped to the section titled "Detecting Forbidden Arrays" and began reading.
"Most Forbidden Arrays that target humans are placed in regions close to natural treasures or lawless lands where evil Cultivators roam free. To detect a Forbidden Array, an Array Master can form an Intermediate Malign Detection Array on their clothes, which will activate if one steps within 25 meters of anything that can damage the Array.
This can be amplified further by using Filter Runes to focus only on threatening Arrays. This is also a common method to defend against enemy Array Masters during an ambush."
William learned a lot from this book. It taught about many different methods to keep him safe from forbidden Arrays, and even ways to counter them. He flipped to another portion of the book that was entirely focused on disabling Arrays.
The System didn't teach William anything about disabling Arrays with his upgrades, only basic knowledge on how Arrays were formed and operated. He had gained power, but didn't know how to use it yet.
"To disable an Array, the Array Master must first identify which Runes make up its component parts. Once the Array Master has deduced one Rune, they have two options. They can destroy the Rune, which may force the Array to cease functioning properly if the Rune is critical, or they can add a new Rune that changes the functions of the Array.
If an Array is designed to launch Earth Spikes in a certain direction, the Array Master can destroy the Rune of Earth that is critical to the Array, or add a Rune of Reflect to reverse the direction of the Earth Spike, rendering the Array harmless either way."
He continued reading for a bit longer, then closed the book and placed it back on the shelf. He noticed the Head Array Master was still present, as he couldn't leave William unattended in a room full of forbidden knowledge.
"Sir, are there any Forbidden Arrays that I can use?" he asked the old man.
"I'm afraid not." the Head Array Master shook his head.
Well, it doesn't hurt to learn one anyway. William looked through the books until he found a highly destructive forbidden Array. It was too complicated for him at the moment, but William would remember it when he learned more about Arrays from his upgrades.
A cursory glance revealed the Array was called the Five Elements Explosion Array, which was essentially the Cultivation World's version of a nuclear bomb. It was formed with three Common Elements and two Rare Elements: Fire, Earth, Wind, Light, and Darkness.
The Array requires a Perfect Rune from each element, two Perfect Runes of Stability, a Perfect Rune of Instability, and five Perfect Runes of Strength. Thirteen Runes formed an ultimate Array that would destroy itself and anything around it within 30 kilometers.
No wonder this Array is forbidden. If it explodes in a city, it will kill millions of people and ruin the landscape for decades. William memorized the Array regardless, since it could be useful in the future. He looked at other books with forbidden Arrays, learning all of them one by one.
Two hours later, the Head Array Master led William out of the Forbidden library and back to the Array Hall, where Will received his Array badge and new robes.
"Do I need to wear this all the time?" William asked.
"Only when you are in the Array Hall working."
William heaved a sigh of relief. The robes were nice, but not exactly his style. Wouldn't he look a bit awkward if he walked around town wearing them?
William thanked the Head Array Master for his time, then asked for Fowley, who should have his Space Ring ready by now. The Head Array Master called for Fowley and congratulated William for his successful tests. He waved farewell before leaving the Array Hall with his bodyguard and the other old man from before.
William didn't have to wait long for Fowley to reach the front counter. The Space Ring was transferred to William, who thanked Fowley for his time.
"Young man, you are more talented in Arrays than I am. If you had an Affinity for Space Magic, perhaps you wouldn't even need someone like myself." he looked content, but there was some uncertainty in Fowley's eyes.
"You were a great help to me, I hope you can keep my secrets and help me again in the future." William responded. He worried that if he wasn't sincere enough Fowley's intentions could change.
Fowley was about to leave, but stopped after thinking of something. "You're not too familiar with how we do things in the Array Hall, so feel free to join me in my room whenever you have an order to complete." he pointed to the room where he met William in the morning.
"Thanks, I will take you up on that offer sometime." William felt Fowley was more easygoing than he looked. Although the man was quite serious, he seemed to truly care about William's well-being.
As an Array Master second only to the Head, William had gained many benefits. A separate room was prepared for William on the balcony, right next to the Array Head's room. It seemed to be covered in Advanced Arrays of disguise, concealment, and the walls were sound-proofed to prevent eavesdropping.
Since he was in the Array Hall, William decided to change into his robes. He used Water and Wind Magic to clean himself, then checked his new look in a simple spell that mirrored his image.
"Oh yeah, I look handsome as usual." William couldn't deny that he no longer looked like a handsome peasant, but a dashing scholar in red and white.
William felt this would be a great time to check the Space Ring for its contents. He placed the ring on his finger and willed it to open, creating a miniature portal that William could use to manipulate the items inside. The process was quite fluid, and there was no longer an Array to block William's gaze.
He leaned his head forward in interest to inspect the inside, but his facial expression changed when he noticed a pale yellow glow from the back corner.