Going back a few hours in time, back to when the fallen had sent the Sky Realm experts into mental collapse with just a look, Shui was crossing through Malirin Forest to reach Silver City. His soul was 70% recovered, but his eyes were bloodshot from the spiritual interference of the remnant intents left in his mind. He had only killed two beasts by accident, but the number of plant creatures he had killed was in the dozens, so it was naturally difficult to suppress their intents even with his strong wood soul.
Alia had given him the option of a short rest once they made it out of Hidden Predator Mountains, but Shui refused to consider it until they arrived at Silver City. He had even planned on continuing to hunt plant-type evolved beasts inside the forests, but Alia convinced him to focus on purifying his mind instead so that he would be able to increase his chances of touching the natural laws of fire.
Fortunately, his energy was mostly untouched since he used pure physical ability to travel this far, and transcendent force kept him from feeling fatigue. Alia protected him from any rude beasts, and since he picked a route that didn't cross into the domains of any great beasts or the beast lords, they were able to leave Malirin Forest around the same time that the Masters began their attack on the fallen.
"Do you think those Masters can suppress it?"
With Alia's clone watching the battle, Shui was able to receive information about the situation in real time.
"That's impossible. They'll be able to damage it by using the natural laws, but none of them seem to have a deep enough understanding to seriously wound it. Well, I suppose it might be different if they have a powerful artifact."
"So it's up to us, I guess."
"Kukuku, are you feeling pressured? We can always let it be until I regain my full power. Though there might not be a country left by then."
"Of course I feel pressure, but it's nothing compared to what I stand to lose if that thing has its way. Even if I have to burn my life here, I'll make sure it can't harm them."
"That's the spirit. Now for the last spurt!"
Once again, Alia gave him a speed boost, but this time he was grateful for it. While Alia went ahead, Shui dashed towards Silver City by himself. As he approached the fleeing Sky Realm experts, Shui put on a mask with a triple layering of 'Conceal'. Given that he was about to use his full power, it was better to disguise himself to avoid possible trouble in the future.
"Wait, stop!"
"If you keep going, you'll die!"
Some of the Sky Realm experts warned him, but their words couldn't slow his steps for a second. When Silver City, or at least what was left of it, entered his sight, Shui saw the fiery spear summoned by Alia and the massive figure of the fallen. There were major differences in its size and shape, but that unsettling, black exterior was the same. He wanted to reach even a second faster, but in his current state there was still little he could do to contribute to the battle. Nonetheless, before heading off, Alia had left him a hint to completing his connection to the natural laws of fire.
"Define your flame."
"Define my flame? You mean my perspective on fire?"
"In essence, yes. In order to make first contact with the natural laws, while it is important to understand how the laws affect reality, you must also create a firm image of the natural laws within yourself. Even among us spirits, there are at least subtle differences in how we use our powers based on the way we view the world. There's no time to stop, so once we start fighting, you should stick to fire-based attacks to help you create the image."
It reminded him of when he was learning how to manifest fire from the Four Elements Technique. This time he didn't have to think as much about how to create fire, but it was still a difficult task that he wasn't sure how to approach. However, the only choice was to find a way to do it.
With a bit of distance left before he reached Silver City, Shui created the void flame and concentrated on condensing it. He could feel the fallen pulling on his vitality, but thanks to a spell from Alia, he didn't have to worry about losing any of his vigour. She apparently hadn't used it on him last time because she thought he would manage somehow, but given his damaged state, she was willing to be generous in this case. The spell would lose effect if the fallen's life-drain ability grew strong enough, but for now it would do.
Once Alia's attack struck the fallen, the Masters trapped by it were released and immediately supported her. News of what happened inside the Spirit Nest had reached their ears, so they quickly put the pieces together and realised that the glowing orb of light battling the fallen was likely the fire spirit who had saved Kate and Mater's groups. The spirit seemed to possess power infinitely close to the True Master Realm, so hope bloomed inside the Masters' hearts.
However, this hope was soon smothered by the fallen's freakish regeneration. Even though every hit from the fire spirit dealt true damage, none of it was permanent thanks to the near-endless vitality of the fallen. As helplessness crept into their expressions, Shui finally appeared at the edge of the city and shot the void flame he had charged up. Though this attack seemed to be from a powerful Master, the four Masters inside the city didn't think it would have much effect. Yet when the attack struck the fallen, it quickly severed its flesh to avoid it.
The four Masters were in shock as they watched the void flame devour the fallen's flesh before vanishing. The void flame was able to burn even their spiritual sense, but their rich experience allowed them to see that it incorporated the natural laws to form a power capable of burning everything. Possessing such a tyrannical flame would make one a peak existence among Masters, but they had no clues as to the identity of the masked person who entered the city.
"Fellow Cultivator, I know not who you are, but I thank you for joining us in stopping this demon beast."
The Argentwave Master greeted Shui, and the other Masters also gestured using their hands to show respect, so he responded similarly. Shui didn't want to interact with them too much and risk exposing his identity, but their strength would be useful in restraining the fallen while he tried to touch the natural law of fire.
To boost his chances, Shui used martial intent to invigorate his mind and body and charged at the fallen with both fists covered in orange fire. Though the void flame was most effective against the fallen, he had to use many types of fire in order to build his image of it. With a single fist, he blew a hole through the fallen's body, but this kind of injury would soon close, so he then unleashed a barrage of flame-covered fists to obliterate a portion of the fallen's flesh.
When the Masters first saw him charge at the strange creature, they wondered why he didn't use his powerful white flame, but his mighty punches proved that he had many means of dealing with the fallen.
"Come. Let us join them."
With the Masters joining the battle, and Alia attracting most of the fallen's attention, Shui set aside a portion of his mind for contemplation.
"I don't know how long this will take, but I'll try to finish as soon as possible, Alia."