The flickering light reflected in Fang Yuan's eyes. His face was full of concentration, his gaze fixed on the semi-finished product before him, straining to stabilise the situation.
Chi!
Suddenly, a sharp, piercing screech exploded out of nowhere. The sound waves stirred the air into a fierce gale, overturning tables, chairs, and bookshelves. Vases crashed to the floor, shattering into pieces. Ink splattered, papers scattered.
The three colours vanished completely. The original semi-finished product exploded into a pool of blue blood, splattering across the surrounding walls.
"Failed again…?" Fang Yuan sighed softly.
These past few days, he had been refining Gu. The Gu was called the Heart-Crushing Infant Cry Gu. It was specifically used to counter the Three Hearts Union Souls.
The Three Hearts Union Souls was a famous killing move of the Dongfang Clan, allowing three Gu Masters to momentarily merge their souls, acting as one, cooperating seamlessly in attack, defense, and movement.
As Fang Yuan experienced these past days firsthand, some of his previously hazy memories gradually became clearer.
He vaguely remembered that Hei Loulan had been badly battered in his fight against Dongfang Yuliang this time around, barely pulling off a narrow victory. Because of the Three Hearts Union Souls, Hei Loulan's side suffered heavy losses.
Later, when Ma Hongyun rose to power, the Three Hearts Union Souls caused him immense trouble when dealing with the Dongfang tribe.
There was even a time when he was set up by a united front and suffered a crushing defeat at the hands of this move, getting captured alive by the Dongfang clan.
Ma Hongyun became a prisoner, but by chance, he met Dongfang Qingyu and captured her heart. She not only secretly set him free but also told him all the secrets of this killing move.
Ma Hongyun returned safely and, working with his wife, the Gu Refining Grandmaster Sheng Ling'er, refined the Heart-Crushing Infant Cry Gu to specifically counter the Three Hearts Union Souls.
On the battlefield, the Heart-Crushing Infant Cry Gu was remarkably effective. Ma Hongyun's side won a great victory, while the Dongfang clan was forced to retreat step by step.
As failures mounted, the Three Hearts Union Souls gradually faded from the stage of history.
By the time of the Five Regions War, with flames of war sweeping the world, the Three Hearts Union Souls was stolen by a Gu Master from Central Continent, improved upon, and rose again. Ma Hongyun directly released the recipe for the Heart-Crushing Infant Cry Gu. Once the world grasped it, they modified the original recipe further, once again cracking the improved Three Hearts Union Souls.
At this point, the Three Hearts Union Souls truly lost its function and was no longer used by anyone.
Fang Yuan had been reborn with memories of his past life five hundred years ago, so of course he knew the recipe for the Heart-Crushing Infant Cry Gu.
But the Heart-Crushing Infant Cry Gu was a Rank Four Gu. Its refining materials were not rare, but the difficulty of refining it was quite high. Despite his almost Grandmaster-level skill in Gu refinement, he had tried over a dozen times and failed every single time.
Letting out a sigh, Fang Yuan stood up and walked over to the window lattice.
The lattice had also been destroyed by the air currents from the failed refining. The glass-like membrane had burst into a large hole. The wind from outside, carrying the scent of grass, rushed into the room through the hole.
Fang Yuan lightly placed his palm on the window frame and channelled a trace of true essence.
Soon, the membrane on the window slowly grew back, solidified again, and completely blocked out the wind.
The wall writhed like a section of intestine, and the craters left from before were filled up and smoothed out. The shattered porcelain on the floor and the blue bloodstains were absorbed.
Such was the convenience of the Big Lizard House Gu.
The Big Lizard House Gu was a Rank Three Gu, an evolution from the Rank Two Lizard House Gu.
The Lizard House Gu was already as big as a bus, shaped like a large lizard with four legs. Inside the lizard was a corridor with several rooms on either side.
The Big Lizard House Gu was like a two-story building, five times the size of the Lizard House Gu.
It had two floors, more rooms, and more space. It was a gift from Hei Loulan after Fang Yuan joined the Hei clan.
He lived and cultivated inside here on a daily basis.
Besides Fang Yuan, there were six Rank Three Gu Masters guarding the surroundings.
They took shifts, equipped with specialised reconnaissance Gu against almost all stealth-based Gu Masters.
If the Shadow Swordsman attacked again, he would be discovered by the Gu Masters before he even got within a hundred paces, exposing his movements. This was an arrangement made after Fang Yuan was once assassinated.
At this moment, Fang Yuan looked down through the window and saw a large number of Gu Masters and mortals busily setting up defences.
Some were digging trenches, some were speeding up the growth of trees and building watchtowers, others were piling up earthen walls… The outline of a tight defensive line was slowly taking shape.
This was already the third line of defence.
The terrain of the Northern Plains was mostly flat grassland, devoid of any natural obstacles. Therefore, in ancient times, when two powers waged war in the Northern Plains, the loser had nowhere to run and would always be ruthlessly pursued by the victor.
A lost great battle often meant the situation was settled, a clan's rapid decline, or even its destruction.
But with defensive lines, it was different.
Once a war was lost, whether retreating, dodging the sharp edge of the enemy, or waiting for a chance to counterattack, these defensive lines would play a huge role.
War was a matter of life and death, directly tied to the rise and fall of a clan. It was extremely perilous and unpredictable. A small accident or a single mistake by one's own side could easily lead to defeat.
At such a time, if a clan retreated relying on defensive lines to catch its breath and stabilise its position, it could regroup and recover.