Investing in My Harem in the Apocalypse Makes Me Stronger

The Blood Crystals filled most of them.

He looked at the enormous amount of resources in front of him before sitting down beside the closest pile.

This time, he would start with the Blood Crystals.

The newly killed zombies still needed to be harvested, so Cain decided not to touch the older Cores yet.

There was little reason to purify them now only to repeat the same process once the others returned with another batch.

Instead, he emptied the Blood Crystals from several boxes and gathered them into enormous piles across the plaza.

Crimson light spread faintly across the dark stone beneath them.

There were more than a thousand.

Cain had stopped trying to estimate the exact number, but the energy contained within the crystals was considerable.

Unfortunately, so was the contamination.

Every Blood Crystal had been formed from the Zombie Race and still contained traces of foreign energy that made direct absorption dangerous.

Cain sat down in front of the nearest pile.

The True Ruin Energy gathered around both hands.

He had purified large quantities of resources before, but never anything close to this amount at once.

Dark-gray energy flowed outward and entered the nearest crystals.

Rather than purifying them individually, Cain divided his control across the entire pile.

The reaction appeared almost immediately.

Dark traces began leaking from within the Blood Crystals before disappearing beneath the pressure of True Ruin.

Cain expanded his control farther.

More crystals became covered as the dark-gray energy gradually spread across the second pile.

His expression grew increasingly focused.

Purifying a single Blood Crystal required almost no effort anymore.

Even handling dozens at once had become relatively easy.

More than a thousand was entirely different.

It wasn’t Mana that became the problem.

Cain possessed more than enough to sustain the process.

The real burden came from control.

The True Ruin Energy was inherently destructive, and Cain needed to erase the contamination without damaging the energy contained inside each crystal.

The larger the number he handled at once, the more carefully he had to divide his concentration.

Several minutes passed.

Sweat began rolling down his face.

His breathing slowly grew heavier, though the flow of True Ruin never became unstable.

Members of the group gradually returned from the battlefield with newly harvested Cores.

They noticed Cain’s condition and kept their distance.

Cain remained completely focused on the Blood Crystals.

One pile after another became clean.

Only when the last trace of foreign contamination disappeared did Cain finally withdraw his hands.

”Haaah...”

His shoulders loosened as he leaned backward.

”Fuck.”

A dull pressure filled his head.

His Mana reserve had barely been affected compared to what he could currently hold, but the mental exhaustion was much worse than he had expected.

Cain opened his Inventory and retrieved a cold fizzy drink from one of the insulated containers he had stocked earlier. The container had been packed with drinks and plenty of ice, keeping everything inside refreshingly cold.

Pssht!

The can opened with a sharp hiss.

He raised it immediately and drank almost all of it without stopping.

The cold sweetness helped clear the dryness in his throat, though the heaviness in his head remained.

Cain lowered the can and looked toward the purified Blood Crystals.

At least the exhausting part had been worth it.

By now, everyone had returned from the battlefield.

The newly harvested Cores had been gathered into another large pile nearby.

Cain stared at them for several seconds.

His head already hurt more just thinking about the next round.

”Let’s rest for a bit first.”

Cain then opened his Inventory again.

Several boxes of sandwiches appeared on the ground, followed by bottled drinks and fizzy cans that had been prepared before they entered the park on Earth.

The group immediately moved toward the food.

They had been fighting almost continuously since entering the Southern Anchor Town, and even those who possessed powerful physiques still needed time to recover mentally.

Cain took another drink for himself.

Instead of joining them, he walked toward the newly harvested Cores and sat down.

He opened the can and took several slow gulps before placing it beside him.

Then True Ruin gathered around his hands once again.

The Cores were fewer than the Blood Crystals, but every one contained far more energy.

That also meant the contamination inside them was denser.

Cain worked more carefully this time.

Dark-gray energy covered the first section of the pile.

Foreign energy was pulled outward and erased as True Ruin passed through each Core.

Cain did not rush as he had already strained his concentration once and knew forcing the process would only increase the risk of damaging something valuable.

The others ate nearby while several people remained positioned around the plaza to watch the surrounding roads.

The ruined town remained quiet.

At the side, Cain was still purifying the Cores.

One batch became clean before he moved to the next.

His concentration gradually became heavier again as sweat returned to his forehead.

By the time the final Core was purified, his shirt had become damp.

Cain withdrew his hands and remained motionless for several seconds.

”Finally.”

Every Core disappeared into his Inventory.

This time, he did not even consider standing.

Two sandwiches appeared in his hands.

Cain opened the first wrapper and immediately took a large bite.

Elara walked over from nearby and stopped beside him.

”You look exhausted.”

Cain swallowed before answering with a faint smile.

”I’m fine, thanks for asking.”

Elara looked at his face that was filled with exhaustion.

”You’ve purified everything almost without resting.”

Cain looked toward the empty section of plaza where the Cores had been.

”Well, it needed to be done.”

She did not argue.

Instead, Elara picked up the drink Cain had left beside him and handed it over.

Cain accepted it.

”Thanks.”

Elara sat nearby while he continued eating.

For the next few minutes, Cain allowed himself to do nothing.

The pressure inside his head slowly faded.

His body was still in excellent condition, but his mind needed time to recover after maintaining such precise control over the True Ruin Energy for so long.

Once he felt better, Cain looked toward the members of the group who had not yet completed their Mana Core preparation.

”Everyone, get ready to absorb these and push your Mana Cores to the Perfected Stage.”

They immediately gathered around him.