Battles along the northern frontier raged without pause, not for a single day.
By holding Yanmen Pass, Gao Chuwu had successfully protected the common folk within the walls. But beyond the pass, the vast northern lands had fallen into a churning sea of guerrilla warfare and counter-raids.
The entire Xuan–Da Command region was ablaze with skirmishes.
The arrival of the Gao Family Village Militia decisively tipped the balance. Ming officers and soldiers—who had initially cowered behind the walls of Xuanfu and Datong—gradually found their courage after receiving report after report of victory. They finally ventured out, beginning to actively hunt down Manchu reconnaissance cavalry in the open field.
As a result, small-scale clashes erupted even more frequently—and far more fiercely.
The battlefield became impossibly complex.
If a true immortal were to hover in the heavens and map troop movements with arrows, they would see the entire Xuan–Da region covered in crisscrossing red, blue, and multicolored lines—so dense and tangled that it would make anyone with trypophobia feel dizzy.
Whenever the Manchus encountered the Gao Family Village Militia, they were beaten every single time.
But when they faced the regular Ming army, the results were often reversed.
Thus, the reports that reached Huang Taiji read:
"Victories and defeats on both sides."
"Though we suffered losses, the Ming army was also heavily weakened."
Huang Taiji frowned.
"The Great Ming is still formidable," he muttered. "It's not yet time to seize the Central Plains."
He waved his hand.
"Enough. We've plundered plenty. Order a withdrawal. Return to the Northeast."
Thus, in the seventh year of Chongzhen, the Manchu invasion of Xuanfu and Datong finally came to an end.
Back in Gao Family Village!
Bai Gongzi's Experimental Car No. 3 slowly rolled out of the Gao Family Village Military Factory.
Senior Chief Technical Engineer Gao Yiyi was practically vibrating with excitement as he gestured enthusiastically at the new vehicle.
"Bai Gongzi, look! This is Experimental Car No. 3, built exactly according to your requirements. To prevent the front from getting smashed again, I reinforced it with an iron plate—and I even added two ramming horns!"
Bai Gongzi stared at it.
The front of the car was… indescribably ugly.
Gao Yiyi's questionable aesthetic sense had led him to bolt a massive, shield-like iron plate onto the front, with two sharp, cone-shaped protrusions jutting out menacingly.
Bai Gongzi looked both amused and pained.
"You're calling these ramming horns?"
"Aren't they?" Gao Yiyi asked sincerely.
Bai Gongzi pointed.
"Aren't these just two iron cones stuck on the front?"
Gao Yiyi said solemnly, "True killing machines value simplicity and practicality."
Bai Gongzi countered, "With something this big, if it crashes into an enemy, they'd be flattened anyway. Do these horns really matter?"
Gao Yiyi shot back instantly, "Isn't there a huge difference between piercing damage and blunt force trauma?"
Bai Gongzi: "..."
For a long moment, he was utterly speechless.
After a painfully long silence, he finally said tiredly,
"If you're that obsessed with piercing damage, wouldn't it be better to just mount two firearms here instead?"
A metaphorical lightbulb exploded above Gao Yiyi's head.
"Oh! You're right! Firearms are far better than cones! Bai Gongzi, you truly are a genius!"
Bai Gongzi tilted his head back and stared at the sky.
"Wouldn't anyone figure that out, genius or not?"
Gao Yiyi was already on a roll.
"If we install firearms, the driver can't operate them while driving. We'd need a dedicated gunner… so we should add a co-driver's seat."
Bai Gongzi nodded thoughtfully.
"With only one co-driver, two guns would still be hard to manage. One should be enough. Reloading on a moving vehicle is troublesome, though. We'd need some kind of rotating bullet-feed mechanism…"
He paused.
"That's a mechanical problem. Wang Zheng is good at that. I'll go ask him."
Inspiration struck like lightning.
Bai Gongzi clapped his hands.
"I need to go redraw the blueprints!"
Gao Yiyi gasped.
"Ah?! Then… you don't want Experimental Car No. 3 anymore?"
Bai Gongzi laughed heartily.
"Nope! It's useless to me now. You can have it and play with it."
Gao Yiyi nearly jumped.
"How can you just abandon it like that? This was built with village treasury funds! Artisans worked day and night on it—at great expense!"
But Bai Gongzi didn't even look back. He ran off and vanished in the blink of an eye.
Gao Yiyi stood there, torn between laughter and despair.
This kid really is as fickle as the wind and rain.
He turned back to stare at Experimental Car No. 3.
Now what?
After a moment's thought, he decided to report the matter to Manager Tan Liwen.
Chief Manager San Shier had already taken a large group of technical personnel to Shanxi. Gao Family Village was now overseen by its second-in-command—Tan Liwen.
When Gao Yiyi found him, Tan Liwen was frowning deeply.
"Damn it," he muttered. "Qingcaogou needs a steam pump, but it's been overcast for two days straight. The solar cars can't run. Using horses or ox carts is a nightmare… what should we do?"
Gao Yiyi seized the opportunity and explained everything.
Tan Liwen's eyes lit up.
"Experimental Car No. 3? It's with you right now?"
"Yes!"
"It can haul a steam pump, right?"
"Of course," Gao Yiyi replied confidently. "It uses a steam engine, just like a train. Smaller, yes—but the power output is enormous."
Tan Liwen laughed in delight.
"Excellent! Strip off all that useless armor. Lighten it up. Attach a trailer, load the steam pump, and send it to Qingcaogou."
Gao Yiyi blinked.
"A… trailer?"
Tan Liwen gestured animatedly.
"Yes! Like those shallow baskets we use for washing vegetables. Make an oversized iron one, hook it to the back, and boom—cargo transport!"
Gao Yiyi hesitated.
"If we mess around with Experimental Car No. 3 like this, won't Bai Gongzi be furious enough to kill us?"
Tan Liwen snorted.
"He said he didn't want it! It was built with treasury funds in the first place. If he's abandoned it, then the treasury reclaims it. Using it to transport goods—isn't that perfectly reasonable?"
Gao Yiyi thought carefully.
"…That actually makes sense."
And so, before long, Experimental Car No. 3—stripped of armor and fitted with a massive cargo bed—set off for Qingcaogou.
To everyone's surprise, it performed exceptionally well.
It didn't rely on sunlight and could run day or night. As long as there was coal, it kept moving. It perfectly compensated for the limitations of the Heavenly Lord's solar cars.
Tan Liwen was ecstatic.
With a decisive stroke of his brush, he approved the following decree:
"The village treasury will fund the mass production of Experimental Car No. 3.
All such vehicles shall be fitted with cargo beds and used for transportation.
They shall henceforth be named: Cargo Trucks."