Maybe it's just a matter of chemistry.

At the entrance of the supermarket.

Under the bright supermarket sign, Yan Wushuang's tense nerves finally relaxed.

He no longer had any strength left in his body, and with a plop, he fell to his knees.

"Are you okay?"

"Ahem... I'm fine, just a little weak." Yan Wushuang waved at Song Zhi and said weakly.

The area around here looks pretty safe, he really needs to take a break.

Song Zhi walked to his side, helped him up and sat him on the ground. After confirming that he was still alive, he walked into the supermarket.

Half a minute later.

Song Zhi came out with two bottles of mineral water and two bags of bread in her hands.

"Here, drink some water."

"Water? I have some purifier here. Let me find it."

Yan Wushuang had his back to Song Zhi and did not see the mineral water in Song Zhi's hand. He just listened to her and thought it was just ordinary surface water.

Although the surface water in some places is not polluted, drinking it for a long time will still cause health problems.

For this situation, large bases will develop purifiers specifically for purifying water sources. By adding a few drops of purifiers to drinking water, there will be no such risk.

However, this purifier is usually only circulated within the base and is very precious. He only has a small bottle.

He took it out because the little girl had just saved their lives.

"Purifier?"

"Yeah, that's it."

Yan Wushuang struggled for a long time to dig out a blue reagent from his pocket, and finally took out a blue reagent, turned around and handed it to Song Zhi.

But when he turned around, he found that the water in Song Zhi's hand was completely different from what he expected.

"Is this the kind of mineral water that circulated before the apocalypse?"