It turned out, monsters from the fifth didn't much like it when you took their slime away. An hour after first deploying the ‘Wuffers’, as the ants had begun to call them, much to the annoyance of the core shapers, they saw for the first time how the slugs would react when they saw someone messing with their precious goop.

How could Solant describe it? They went absolutely, one-hundred percent, without exception, gonzo crazy.

A fat toad monster hopped around the corner and saw the wuffers happily huffing and puffing, soaking up the slime and purifying it, and grew still. Naturally, the ants had sprung into action, recovering the slow-moving pets and taking up a defensive formation.

What they didn’t expect was for the frog to unleash a mighty croak, the explosive exhalation filled with mindless rage, before it hurled itself headlong toward the massed ant position. Such was its anger, the monster fought completely heedless of its own survival, throwing itself recklessly into the jaws of the soldiers, trying to crush them with its mass whilst it lashed out with powerful legs, lashing tongue and toxic bile.

Many were wounded, despite the fight being thousands against one, and Solant was not pleased.

In the midst of reprimanding her soldiers for their slow reaction, and blaming herself for not foreseeing the situation, she sensed something might be a little off, and stared hard into the haze-filled depths before them.

“Let’s pull back and fortify,” she ordered crisply. “I want tunnel fort three dash two constructed in five minutes.”

“That build is allotted seven minutes,” her lead carver and fellow broodmate, Subutant, stated.

“We don’t have seven,” Solant replied shortly and the carver dashed away, issuing a flurry of instructions to her fellow builders.

“What do you see?” Sumant asked, bracing in the frontline along with the other soldiers as they began an ordered, step by step retreat toward the mountain fortifications.

“That frog would have been heard for kilometres through these tunnels,” Solant replied, watching the haze intently.

“You think it was calling for reinforcements? It didn’t seem that intelligent.”

“I don’t think it was calling for them, but I think they’ll come anyway.”

In just a few minutes, the basic outline of the tunnel fort was complete: sturdy walls, narrow opening, firing lines for spells and acid, along with channels for pulling back the wounded, had all been formed.

Just in time.

The ants had barely taken their positions when the haze seemed to thicken, imperceptibly at first, then in a rush, growing so dense that Solant could barely see ten metres in front of her.

“We need wuffer mist,” she ordered, and the core shapers grudgingly responded, the pets raising their tendrils and happily wuffing as they unleashed the sparkling blue vapour.

It was enough to prevent the miasma from flowing through the gap, but didn’t break through the haze that filled the tunnel in front of them. As it turns out, it didn’t have to.

Every ant tensed as they heard the first roar, then the second, the third, and more, and more. Squelching, wet gurgles of rage bounced off the slime-coated tunnel walls to reach them as Solant lost count of the different monster calls. There were dozens of them.

“Ice and fire the tunnel, one minute. Quick!” she snapped.

Mages dashed forward. The tunnel ahead was swept with an intense blizzard as fifty ice mages coordinated to drop the temperature well below freezing, pelting every surface with a barrage of frozen water. Thirty seconds later, they pulled back and the fire mages stepped forward, igniting the air itself in a furious blast. Rock groaned and cracked at the rapid temperature shift and the sludge sizzled.

The monsters screamed even louder, and much, much closer.

“Brace!” Solant roared as the fire mages cut off the blaze at the last second and scuttled backward, huge soldiers rushing forward to take their place.

The wall of chitin was four soldiers deep when the first slug arrived, screeching, its circular maw wide open and a ‘tongue’ of razor-sharp barbs projecting wildly forward. Prepared for the injuries, the soldiers lunged and chomped, their mandibles sizzling as they bit into the toxic flesh. Heedless of the wounds, the slug pushed forward, discharging a burst of slime from the pores on its back.

A flood of water from the mages cleaned out much of the goop, but it was stubborn and more than one soldier battled on with a sizzling, clinging patch of goop on their back.

The core shapers stepped up and their pets came alongside them. Opening their mouths wide, the wuffers shot forth blasts of pure gel that clung to the ooze whenever they came into contact, acting to counteract and neutralise the sludge.

The slug died, still burbling in fury, and the soldiers hastily pulled the Biomass into the temporary fort. The wuffers descended on it with apparent joy, settling atop the remains of the creature and absorbing it.

“Wuff, wuff, wuff!” they chortled.

Then came another slug, and another, then a toxin elemental, then a toad, then more, and more and more.

When it finally finished, Solant’s force had been battered, bruised and almost broken a dozen times. The list of injured ants was far too long, and more than a hundred had fallen in the furious fighting. The price they had paid for the pitiful progress that had been achieved made her want to chalk up the battle as a loss, but in her heart, she knew it had been worth it.

Piles of fifth stratum Biomass, dozens of cores and the lessons learned were a rich reward indeed, not to mention what they had learned about their new weapons against the sludge.

Without the purifying mist and gel, it would have been ten times as difficult to hold off the assault. The sludge monsters had willingly thrown their lives away to try and coat the ants with slime and acid, to fill the position with corrupting miasma. Without the wuffers counteracting the poisonous mana, the ants would have been fighting abdomen deep in sludge, a battle they were sure to lose.

Even more promising, the transparent jelly-caterpillars were only tier three. The next time Solant returned, she was determined they would be tier six.

“Prepare the retreat,” she ordered. “I want the most wounded to be returning under escort in the next two minutes. Everyone who is healthy will remain here and form the defensive line as we pull back.”

She turned to the core shapers.

“You did extremely well, and your pets have proven invaluable. This expedition has been a resounding success. Retreat immediately with your charges, I do not want to risk them in the slightest.”

As the core shapers moved away with their strange pets wiggling and humping along beside them, Leonidant, Subutant and Sumant gathered around their general.

“What do you think just happened, general?” the carver wondered. “We’ve never seen behaviour like that from the fifth’s monsters.”

“I have never been in a fight that intense,” Sumant admitted. “We were an antenna's breadth away from being overrun at the front.”

Solant considered for a while.

“We aren’t the first to think of cleansing the toxic mana of the fifth,” she said, “yet nobody else seems to do it, that we know of, at least. Why do you think that is?”

“Because the slugs go completely nuts whenever you try it?” Leonidant muttered.

Solant nodded.

“I think so. What we just experienced is but a taste of what awaits us in the fifth. The second we attempt to cleanse a single centimetre of corruption, every monster in a wide radius will rush at us in that same murderous rage.”

Sumant shuddered.

“That’s terrible.”

“It’s predictable,” Solant corrected, clacking her mandibles thoughtfully, “and predictable is always to our advantage.”