It took Percy several more hours to cure the rest of the villagers. Not all of them advanced like the girl, but many did. Especially the older ones or those with the most poison accumulated in their cores.

By now, Percy was in a lot of pain, his host’s soul already beginning to crumble. He had to keep shifting his soul mana around the dying vessel to hold it together just a little longer. Despite the pain, a content grin tugged at his lips. He hadn't known these people for long, and his efforts hadn't permanently solved their problems, but even this small act of kindness brought him a sense of satisfaction.

“Kerez dim laat!! Kerez dim laat!!” they chanted over and over, their joy surpassing even his own.

Waving them farewell, Percy took off, determined to accomplish one more task before his body gave out. He doubted it would make much difference, but he wanted to help the locals one last time before returning home. Retracing his steps from two weeks prior, he flew along the river. Before long, his destination came into view – the giant vent spewing brown gas into the air.

Guessing this was the closest source of pollution to the village, Percy’s plan was to filter as much of the substance as possible before his host expired. As he approached the colossal geyser, he noticed more of his kin – this time including a few larger ones with Yellow cores. However, none had the distinctive grey fur of his host, indicating that the creature he was inhabiting was likely an elder, even among others of the same grade.

‘Hopefully we’re close to a promotion too.’

Drawing nearer, Percy’s vision was soon obscured by the dense cloud of gas, but he managed to orient himself toward the hole by tasting the concentration of the toxic substance around him. By now, he had to rely on Mana Sense to locate the other furballs, the population of which grew denser the closer he came to the source of the gas.

At least, that was the case at first. Past a certain point, the strawberry flavor in the air grew overwhelming, almost reminiscent of the syrupy sludge he’d extracted from the villagers’ cores. As he pressed on, the number of Orange cored beasts began to dwindle. Here, the fog was so thick it was beginning to hinder his movements, the current pushing him back. The sweetness in his mouth gave way to a spicy sensation as his core began to burn.

‘Wow, I guess even our species have their limits.’

Not that he cared much about his health – he only had minutes left anyway. Unlike his Yellow cored kin, who were unwilling to venture further, Percy pressed onward, diving deeper against the flow. Ignoring the pain in his sternum, he took deep breaths, trying to rid the world of as much of the toxic gas as he could manage as a final gift to the villagers.

The remnants of his host’s soul began to shatter, the knots of soul mana unravelling. Percy could already feel the ethereal cord linking him to his main body on Remior pulling him back. He resisted for as long as he could, until it seemed he was about to lose the battle, when something changed.

His body began to burn more intensely than before, internal pressure threatening to tear him apart. Percy grinned, recognizing the sensation – one his familiar had experienced in the past. Looking inward, he quickly confirmed his suspicion. His body was saturated with dense Yellow mana, though parts of it were dimmer than others. His organs were fighting a losing battle, struggling to purify the toxin into a state his core could handle.

However, something began to shift as strands of Green mana started to form in his sternum. As he had hoped, his host had lived just long enough to reach the boundary of his next promotion. The reckless baptism in the toxic fumes had proven to be precisely the catalyst required to push them over the edge.

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Soon, the Green strands coiled together, consuming the Yellow mana around them, as his core shifted colours, burning more fiercely than ever before.

‘Keep it together old cat!’

Usually, a core advancement was a joyous occasion. However, this was perhaps one of the few cases where it wouldn’t do anyone much good. The creature’s remaining lifespan would be tripled, but three times zero was zero. It was still going to die within the next minute.

As for Percy, his host’s advancement only complicated matters, hastening the unravelling of the fragile bonds joining their souls. That said, he hoped to last long enough to harness this opportunity to do some real good.

‘Just a few more seconds…’ he smiled wryly.

Now that the furball had advanced, they could consume a tremendous quantity of the toxic gas. Strictly speaking, the vent was too large for a single creature to filter by itself, whether it was at Green or even Blue. However, there was one critical exception where a beast could consume far more than normal.

At the moment of its advancement!

Back when Micky had evolved to Orange, Percy and the crow had spent all night scouring the Whistling Woods, feeding the bird anything they could find so it could rebuild its body to suit its new grade. This time, the furball had advanced to Green – two grades higher – and its diet consisted entirely of the toxic brown gas. Just how much of it would it need to consume to complete its transformation?

Well, Percy intended to find out.

Fighting against his crumbling body, Remior’s pull and the pressure from the vent, he opened his mouth, inhaling the gas as forcefully as he could. Normally, his lungs would have filled in an instant, but now his body hungrily absorbed every bit of material that entered, breaking down the toxins into nutrients necessary for growth.

Soon, the clone transformed into a ravenous vortex, greedily sucking in the brown fog like a drain at the bottom of a tub. He could feel his body swelling at an alarming rate, doubling in size within half a minute as the remaining shards of the dying soul grew just as quickly as they crumbled.

This pace wouldn’t last long – his vessel was already nearing its new limits – but the massive intake of mist triggered another change. The pressure from the vent was no longer enough to push him back, his expanding body beginning to accelerate toward it.

Having absorbed enough nutrients, the flow of gas began to slow, but Percy refused to let it. He forced his body to continue drawing in every last particle of poison it could, even as he hurtled dangerously toward the ground.

He slammed into a stone wall with a deafening crash, feeling both bones and rock shatter as the impact knocked the air from his lungs and sent his body rebounding. More impacts followed, each collision wreaking havoc on his flesh as well as the surrounding environment.

Percy heard more stones crashing down as sections of the vent’s walls crumbled, but he didn’t pay that any heed, focusing solely on maintaining his grip on the dying soul and inhaling more fumes with every ounce of willpower he had left.

By now, every bone in the furball’s body had turned into mush, as a bunch of boulders fell on top of him, pushing him down. Percy’s lungs felt like they were on fire, the pungent substance overwhelming even his newly upgraded constitution.

‘I hope that was enough…’ he thought, his consciousness finally slipping out of the dying vessel.

Percy knew his actions didn’t truly amount to much.

The furballs he had placed inside the villagers’ houses would leave sooner or later. The cores he had cleansed would eventually end up polluted again, and the poison he had consumed inside the vent would hardly make a dent. And even if he ended up helping out the people in that village, just how many more villages like that were scattered around this world?

But he didn’t regret trying.

Everything he’d done would buy these people some precious time. With higher grades, a cleaner environment and healthier bodies, the ones with the pure affinity would be able to produce more cyan powder too, extending everyone’s lives even more. They might still die, but the few years he had bought them mattered. They mattered just as much as when he’d killed Mixcoatl, or when he’d preserved his friend’s soul to create his familiar.

Percy wasn’t strong enough yet to free the people of Huehue, or to cleanse all the poison in this world…

But he would do what he could, to help as many as he could…

Why?

Because he felt like it. Micky was his friend, and he’d grown fond of the natives here too.

Wasn’t that what magic ultimately was?

The power to exert one’s will on the world!

‘I’ll keep growing stronger and… one day, I’ll have the power to make a lasting impact.’