Under the precise operation of the construction robots, the two geothermal generators were successfully activated and smoothly integrated into the shelter's power grid.
At this time, Su Wu had just finished a call with a resident of the official shelter. From her, he received a packaged data file.
He skillfully received and saved it before immediately adding all 29 songs from it to the player and playing them.
A soft female voice filled the control room, dispelling the silence. The melody seemed to transport him back to a summer of lush green trees, full of vitality and comfort.
"This song is pretty nice," Su Wu murmured, feeling a wave of nostalgia.
By his calculations, it should be early summer now. In normal times, this would be the season for sweet, ice-cold watermelons, when dense, green leaves cut the sunlight into scattered patches, and gentle breezes lulled people into midday naps.
But now, all of that was nothing more than a distant, irretrievable dream.
What remained was an environment where temperatures had doubled, reaching 60 or even 70 degrees Celsius.
Under such extreme conditions, vegetation had no chance of survival.
Adding to that were the global superfires, droughts, and the fog layer—over ten kilometers thick—that shrouded the sky.
At this point, the world's remaining surface vegetation was likely less than one percent of what it once was.
Snapping out of his thoughts, Su Wu noticed that the installation of the geothermal generators had been completed.
Ye Xi sent him a website link, along with an account and password.
Clicking the link and entering the credentials, Su Wu found himself logged into an online marketplace displaying dozens of pages of tradable goods. His account had a spending limit of seven million—exactly the amount he had earned from the generator sale.
"It's time to reap the rewards," he thought, sitting up straighter, his eyes sharpening with focus.
The future growth of his shelter depended on this crucial decision.
After spending some time browsing the marketplace, he formed a rough plan.
His shelter had already been expanded to three underground floors.
The first floor housed the hydroponic farm, which provided rice, vegetables, and fruit.
The second floor covered daily living needs, water supply, and small-scale mechanical parts manufacturing and maintenance.
The third floor had the infrastructure for a breeding facility, which only needed an initial investment in poultry and fish, along with some starter feed, to begin producing fresh meat continuously.
From a functional standpoint, the most urgent priority was officially launching the breeding facility.
"For the first batch of purchases…"
"Five thousand hatchable chicken eggs, two thousand hatchable duck eggs, and two thousand fish fry of different species."
"And about five tons of emergency feed."
Compared to already hatched chicks and ducklings, eggs were significantly cheaper.
Of course, raising them to maturity would take longer.
But Su Wu could afford to wait.
His storage already contained enough frozen meat and canned goods, ensuring that there was no immediate meat shortage.
Moreover, alternative feed sources like grass and algae also needed time to grow, aligning perfectly with the incubation period for the poultry.
The total cost of this batch was around 30,000—a negligible amount compared to his multi-million spending limit, yet it solved his most pressing issue.
"Next, I need a lot of fertilizer."
Whether for hydroponics or feed crop cultivation, fertilizer was indispensable.
While Su Wu had some reserves, they were tied directly to the survival and foundation of the shelter. Self-production was still out of reach.
He would need a large supply.
Additionally, fertilizers could be used to manufacture explosives.
While he hoped it wouldn't come to that, survival in a post-apocalyptic world often depended on having options.
"It doesn't spoil anyway."
"This is a rare chance—might as well stock up."
Determined, Su Wu increased his original purchase plan tenfold.
He placed an order for 500 tons of fertilizer, instantly wiping out half the stock in the online marketplace. The cost? One million.
"Next up: construction materials."
"Cement and steel rebar."
Despite using mostly salvaged construction waste and stone for his shelter's expansion, he still needed cement for reinforcement.
However, his last batch—two truckloads—would only allow him to dig down to the fifth underground level, around 40 meters deep.
That wasn't nearly enough.
Especially considering that the official second-phase shelter project was already reaching 270 meters underground.
Yet when he checked the marketplace, he realized the official shelter might not be as resource-rich as he'd assumed.
The cement inventory was only 500 tons.
At 20 yuan per bag, even if he bought out the entire supply, it would only cost 200,000 yuan.
"Not bad," he thought.
"That's ten times more than my last batch."
"Better not get too greedy."
Though slightly disappointed, he quickly adjusted his mindset. Given the ongoing construction of the official shelter's second phase, it was likely that even these 500 tons had been scraped together from multiple sources.
Being able to purchase any at all was already a win.
There was better news regarding steel rebar, though—it was in ample supply.
Su Wu wasted no time, purchasing 1,000 tons in one go.
"Still 1.7 million left."
Staring at his remaining balance, he knew there was no point in saving it.
With policy shifts being unpredictable, the value of his credits could be erased at any moment.
Better to convert them into tangible goods while he still could.
After some thought, he set his sights on something he had long considered—sugar.
This time, there were no purchase restrictions, so he immediately ordered 20 tons.
To go along with it, he added 10 tons each of salt, gasoline, and diesel.
Daily necessities like toilet paper and soap were another must-buy. For long-term survival, the stock of these items needed to last at least several decades—he ordered 1,000 boxes.
He also stocked up on drones, high-end and low-end chips, wires, light fixtures, and other essentials for his shelter's automation systems.
With each order, his balance dwindled rapidly, until only about 400,000 remained.
"That should cover everything essential."
"The rest can go to cigarettes, alcohol, and medicine."
Though he personally disliked smoking and drinking, he understood their value.
For many, tobacco and alcohol were practically universal currencies.
Medicine was equally crucial—not for trade, but for survival.
While it lacked the addictive draw of tobacco and alcohol, it could save lives and alleviate severe pain in critical moments.
Any survivor in this world knew the true worth of medicine.
The only drawback was its expiration date—unlike liquor or cigarettes, medicine lost its potency over time, and in some cases, expired drugs could even become harmful.