After Kourosh was assured of the success of his psychological warfare and secret diplomacy, the time for the final visit arrived.
A visit to the beating industrial heart of his army.
In the silence before dawn, accompanied by Cambyses and Arash, he left the camp.
This time, their journey was not with the grandeur of a royal caravan, but in silence and with their faces covered.
They passed through secret mountain paths.
This journey was a return to the source of the power that was destined to decide the fate of the war.
Upon reaching the entrance of the valley, there was no longer any sign of that small, experimental workshop.
The hidden valley of the Zagros had transformed into a small but bustling industrial town.
The smoke from dozens of large and small furnaces filled the air.
The incessant sound of hammers, the roar of bellows, and the shouts of master craftsmen played a wordless symphony of creation and destruction.
Cambyses and Arash stared at this scene in astonishment.
On one side, workers were crushing iron ore.
On the other, carts full of newly made weapons were being transported to cool storerooms in the heart of the mountain.
This was a war machine that worked with flawless order.
Kourosh, with confident steps, led them towards the main weapons depot.
As the heavy wooden door was moved aside, an unbelievable vista was revealed before them.
Thousands of cast iron spearheads, like a forest of steel, were arranged on wooden shelves up to the ceiling.
Beside them, thousands of short swords in leather sheaths awaited the hands of the warriors.
Arash stepped forward with trembling steps.
He drew one of the swords from its sheath.
Its gray and matte blade reflected an ominous light.
With a voice trembling with excitement, he said, "Unbelievable..."
"In my entire life, I have never seen such a huge volume of uniform, high-quality weapons. This workshop alone can arm an army to the teeth."
At the end of the depot, dozens of newly assembled war chariots stood in a line.
The scythe-like cast iron blades attached to their wheels gleamed under the torchlight.
Cambyses ran his hand over one of the blades.
"These... these will mow down the enemy's ranks."
"This is no longer a chariot; it is a killing machine."
He looked at Kourosh, with a gaze that was a mixture of pride, admiration, and perhaps a little fear.
"My son, what beast have you unleashed from the heart of these mountains?"
Kourosh smiled.
He led them towards the main workshop, where the "Shahbaz Furnace" roared with all its might.
Garshasp, the master blacksmith, with a face covered in soot and sweat, but with eyes bright from the fire of the furnace, came to greet them.
"My lord! Your presence gives us strength. As you commanded, production continues without pause."
Kourosh warmly placed his hand on his shoulder.
"It is you and your companions who are forging our victory with your hands, master. Every strike of your hammer is a blow to the enemy's heart."
He then asked with a serious gaze, "What is the news of the special projects?"
Garshasp replied with excitement, "The crossbows are being prepared, my lord. They have unbelievable power."
"Yesterday we tested one. Its bolt went through the leather shield we had set up!"
"There are some problems with it, but we are all hopeful of solving them."
Then he pointed to a corner of the workshop that was covered with a thick curtain.
"And those giants... the ballistas... their construction is also nearing completion."
"The carpenters and engineers have worked day and night."
"We have not yet finished testing this wooden and metal beast. It will be ready in a few weeks at most."
Kourosh turned to Garshasp.
"Master, continue your work. Faster, more. Our army needs every single one of these weapons."
Then he turned to his father and his commander.
"Now is the time to return. We have the tools of victory in our hands."
They left the valley in silence.
Behind them, the Shahbaz Furnace continued to roar.
The beating heart of Kourosh's industrial revolution was pouring molten steel into the veins of the future Persian army.
Their technological superiority was no longer a theory.
It was a deadly and undeniable reality.