Why did Darius plant the Soul Curse here? Well, the reason was quite simple. The true level of power and the true difficulty would present itself starting from the Adept hives.

After he planted the Soul Curse here, it would take some time to spread competently as different hives would infect each other over time. However, as time was the most precious thing now, Darius would have to use shortcuts to achieve his goals within the time limit.

Namely, by poisoning the Adepts here.

Once he rose back up, he would begin the slaughter from where Gunner and co had left off, some Insects that they would intentionally allow to survive would then proceed to send news down about the culling.

This would make it so that those down below would start to panic due to the power of the three, and they would also send out messengers further down.

With 90% of the Adept hives that Darius planned to poison, the 'messengers' in this sense would be sure to infect the Master hives, who would, in turn, forward the message, thus infecting Grandmaster hives.

By the time Darius worked his way down, most of the high-level hives should be suffering from the 50% weakening effect. With his power and Gunner's taking care of them should become possible.

Ultimately, it would boil down to whatever secrets or trump cards the Insect race had managed to keep secret. Darius had no illusion that despite God Krona's information stating that things should proceed smoothly for Darius, that it would be that simple.

This was not due to any logical process, but mostly Darius' own gut instinct. It wasn't even his Spiritual Senses from high Luck or anything, just the kind of common sense that anyone from Earth would have in situations like these.

An Earthling knew that when something looked too easy in a dangerous situation, there was a very high likelihood something else was brewing in secret that would absolutely decimate an individual unless some cosmic powers saved their skins.

Since Darius only had the Goddess of Luck on his side, he wanted to make some preparations ahead of time so that he wouldn't be left at her mercy, forced to hope that she would be in the mood to save him from a certain death situation.

Darius then moved through this level of the underground, planting the Soul Curse on any Insect he found as long as he detected it was hale and hearty. Once it returned, it would naturally infect the rest of its hive, so any healthy Insect he encountered indicated that it was from a yet uninfected hive

Since he was just making one cast before teleporting away, it took him only a few days to accomplish his goal.

Gunner and Xela followed along with curious expression, partly understanding what Darius was trying to achieve and partly doubtful if things would pan out so perfectly.

Once done, they returned to where the Branded Servant Duo had stopped their work. Darius noticed that they had done a good on extending the network as far as here in the meantime.

With how well Solena and Miranda had fortified this 2% of the entire underground, they could quickly spring forth and expand to places that Darius had already conquered, so they got to that.

Darius had the group split up for now to pursue different paths, but not before he had both Branded Servants learn the Insect Blood Curse which would allow them to instantly kill any Amateur or Journeymen bug.

Of course, they were free to use any other means they had at their disposal as well.

Darius hadn't let Gunner and Xela work while he had been infecting the Adept hives because of two reasons.

The first was to let the duo memorize and identify the hives that were infected so that they could avoid them for the time being, as they were their precious disease carriers.

The second reason was to form symmetry.

If Gunner and Xela started on their own paths before him, their overall progress would not be organized, leading to disorganization in their overall progress.

The moment each went on their own paths, Darius could perfectly monitor the progress each was making and react in case there would be a problem, solving it on the go.

And so, the Great Insect Genocide began.

Darius appeared before a large hive with hundreds of Amateur and Journeyman bugs. Instead of using the Blood Curse, since it was a single target spell, he simply slammed the butt of his dragon scale staff against the ground and cast many of his AOE Journeyman spells.

Flame Pillar, Wind Blade Barrage, Water Torrent, Earth Wave, Icy Wind, Sonic Blast, etc!

With 400 points of Intellect and his various equipment and modifiers, the smallest amount of damage dealt by Darius was in the 2,000s.

This was an instant kill for such low-stage bugs, making it such that he didn't even need a few seconds to deal with the entire hive using only a smidgen of mana.

As for Gunner, he just entered a hive and sneered as the insects rushed over to him and lay their teeth in his flesh and suckle his blood in order to sate their insane hunger. He would jump stomp a few times, using Earth Stomp to flatten the entire area.

Whatever remained would be blown up by him when he shot his Omega Blow into the remains, causing a small explosion of green light. Whatever still lived by this point would no longer exist in the world.

As for Xela, she was more straightforward. She didn't have much in the way of offensive abilities and her archery was best suited for dealing with singular but powerful targets, not hundreds of weak and incompetent ones.

As such, she just channeled her Intermediate Psychomancy, using telekinetic waves to crush as many Insects as she encountered with her domain.

The Elven Princess also used her Mind Control in conjunction with the information Darius had collected about how their hivemind worked, planting 'viruses' in their mind that made some bugs fight and devour each other.

Watching the Insects rip each other to shreds was quite an experience, but Xela firmed her will and saw it through.

She was aware that both Darius and Gunner were quite worried that she would slow them down due to her lack of offensive capabilities, but she had spent the 21 days that Darius had been away coming up with a solution to how best to contribute in such an endeavor.

And this was her answer!