In this post-apocalyptic world, I unexpectedly became a star galaxy master.

"Looks like the extreme heat is coming tonight."

After turning off her phone and reading the news, Hongtang began preparing for the extreme heat.

Put away the sheets, blankets, pillows, and slippers.

Toiletries, tissues, and trash cans, please collect.

Solar lights, induction cookers, and refrigerators are available.

Cat bed, food bowl, water bowl, toys – put them away.

After thinking about it, he took away all the original furnishings in the small room, including the bed, cabinets, chairs, sofa, TV, curtains, and air conditioner.

This cost her four months' rent.

Watching the numbers slowly rise on my phone's thermometer, the temperature is about to break 60°C.

Hongtang clapped her hands. "It's all set. We'll be living in this space for the next few days. Who knows how hot it will eventually get?"

According to my sister, the extreme heat can reach 75°C, and if you "die" in your sleep in the middle of the night, you're really dead. She has a cheat device that keeps the temperature at a constant 28°C inside; wouldn't it be wonderful to be inside?

Although people's heat tolerance has improved after years of enduring scorching heat, the highest temperature in previous years was only around 55°C. Now it's almost 60°C, which many people will find unbearable, especially the elderly and children.

The sound of ambulance sirens never stopped outside all day, coming from workers in the surrounding buildings. Three ambulances came to the office building where Hongtang worked.

Accompanied by the piercing sound of a horn, Hongtang carried Ha Ge into the space.

[Ding, congratulations host, system upgrade complete, now starting up.] The cold, mechanical voice sounded different this time, seemingly carrying some emotion.

"Sister, welcome back! I missed you so much!" Great! The free laborer is finally back.

Then Hongtang was overjoyed again, "Wow, this time my sister can be holographically visualized! But why are you only wearing pajamas?" Before, she could only hear her sister's voice, but now she can see her image.

What appeared before me was the image of a little girl, with two cute pigtails, wearing only a small tank top and briefs.

[Oh dear, after the next upgrade, little sister will have a pretty dress to wear! Host, keep up the good work and trade more!] A soft, sweet voice, with a hint of coquetry.

"Yes, yes, I'll do my best for my little sister's pretty dress," Hongtang promised, patting her chest.

The next time my sister levels up, she needs to reach level 6 merchant, which requires her to make over 610 million transactions.

[Ding! Congratulations, host! You have been awarded a level-up gift pack.]

[Ding, congratulations host, you have activated the "Transaction Search" function.]

[Ding, congratulations host, the "automatic payment" function has been activated.]

[Ding, congratulations host, you have obtained a "payment in installments" credit line of 1 million interdimensional coins.]

[Ding, congratulations host, you have obtained...]

A series of dripping sounds rang out, leaving Hongtang somewhat overwhelmed.

“Sister, let’s stop for a moment. You said before that after you level up, you will get more information about ‘energy’. Tell me about it now.” Hongtang wasn’t in a hurry for the other things, but she was very concerned about this.

With frequent use, she felt the power of energy within her body more and more, but she didn't know how to use it.

Ugh, this is really heartbreaking.

[Host, your sister learned from the 'Main System' that energy has different names in different planes, worlds, interstellar spaces, and races. These include things like source, element, element, energy, ability, superpower, special ability, magic, spiritual power, mana, profound power, and innate talent. But fundamentally, they are all a naturally existing elemental energy. It is generally divided into five attributes: metal, wood, water, fire, and earth, as well as three variant attributes: thunder, wind, and lightning, and other special attributes such as mental power, space, light, darkness, and invisibility, which are relatively rare.]

This elemental energy appears visually as tiny particles floating in the air, each with a different color. Beings capable of capturing these particles are typically said to have 'awakened.' The more elemental energy they acquire, the greater their abilities. People generally categorize awakened energy into levels based on experience, though the specific methods vary.

The magnitude of power exhibited by each energy varies, depending on the awakened individual's level, control over the energy, their own strength, and the characteristics of the element. Generally, at the same level, metal and fire are stronger than wood, water, and earth. At the same time, lightning counters metal, so it cannot be said definitively that one energy will always be stronger than another. When used properly, they can all produce unexpected effects.

Here it comes, here comes the important part. Hongtang took out her notebook.

[Metal can manipulate various metallic elements, changing its form at will, and is both offensive and defensive. Wood is compatible with plants, has a growth-promoting effect, and exhibits many types of mutations, such as purification, healing, and absorption. Water...]

Water and ice can be transformed, depending on the awakened individual's comprehension and level. Generally, high-level awakened individuals can even create their own elemental tactics, such as forming their own elemental domains...

[Mental power; capable of attacking and controlling a person's brain and body; can also conduct 'reconnaissance' within a certain range...]

[Space is the most special type of space. It's generally used for storage, but each awakened individual's situation is different. Factors include the size of the space, whether it can support living things, and its ability to preserve food. Higher-level awakened individuals can also retrieve items remotely or awaken spatial skills such as spatial blades, spatial manipulation, spatial sealing, spatial movement, spatial traversal, and even flight...]

[Besides using more elemental energy for practice, leveling up can also be aided by external energy sources, such as energy stones, energy water, and energy plants... Host, that's all your sister knows for now. She might get more information next time she levels up.] The younger sister's sweet, childlike voice carried a hint of playfulness.

Hongtang listened with great interest, filling her little notebook with notes.

Regarding the use of energy, perhaps she can broaden her thinking by watching related novels or movies in the future?

"Okay, don't worry, little sister. I'll work hard to sell vegetables and level up." Hongtang knew her sister was trying to urge her to sell more, but she didn't call her out on it. This would benefit both of them.

Putting away her notebook, Hongtang said, "Little sister, don't we still have a self-service transaction card? Let's use it now. I want to see if we can buy high-tech infrastructure equipment."

If she doesn't have a good life in the rescue zone in the future, she can build her own "doomsday fortress," so she needs infrastructure.

She had already asked Xixier in the high-tech dimension, but her research focused on everyday life, so she didn't have the information.

[Host, you can use the 'Trade Search' function. Enter keywords, and the system will automatically match corresponding merchants.]

"Okay, help me with it, little sister." It's so nice to have a little sister around; she only needs to give orders.

[Okay, host. The system is searching for interdimensional merchants tagged with 'high-tech, infrastructure equipment'. Please wait.]

[Host, the system has automatically connected.]

"Hello, Ms. Xiaotang, I didn't expect to meet you again!" Hoss on the transparent display screen had a bright smile on his face.

Hongtang: So why did she waste a self-service transaction card?

Isn't Hoss a weapons merchant? Why is he involved in infrastructure construction?

Hongtang gave an awkward smile. "Hello, Hoss, do you have any infrastructure equipment?" She got straight to the point. "I remember you're a weapons dealer."

Hoss smiled mysteriously, "Yes, I used to be in the infrastructure business, but I couldn't make it anymore, so I became a weapons dealer."

"I have a set of infrastructure robots that can traverse mountains and seas, and build across the entire interstellar space. I guarantee you'll be satisfied."

Hongtang: "......"!!