Fire iron. Magma crystals. Ash shards. Pyrestone. Along with cores of the demons themselves, these make up just a few of the precious resources that make the third stratum such a hotbed of conflict. For as long as the powers of the world have known of the demon layer, they have fought over it. Territory secured here has always been precious, especially in those areas where the mana flows thick, and the treasures are abundant. Due to a number of factors, such as the difficult of coexistence with the demons and managing the fallout of their endless battles, securing a safe holding is a constant drain on whoever should attempt to do so. The borders between the various powers are thus in a constant state of flux, rich mining grounds changing hands on a weekly basis. Though the rewards are well worth it.

Fire iron. The precious ore can be found within the stone between layers, or indeed in molten pools mixed with lava. Filled to the brim with fire attuned mana, the weapons forged from this material can become so hot that there are reports of them melting the armour of the foes they were used on while there were men inside it. When properly utilised, it's even possible to forge a suit that would allow a being to dive into molten rock and come out unscathed.

Magma crystals are far rarer. An infused form of quartz, these crystals are so dense with concentrated mana that they can spew forth a flow of lava for hours at a time without needing to be recharged. It was the Legionem Abyssi who were the first to learn how to safely carve slivers of from the gems and apply them to the tips of arrows, a trick that might have been better had it never been learned at all.

Ash shards. A grim material that skirts the edges of the forbidden. The power of ash is a breath away from that of disintegration and annihilation. Capable of dissolving a person whole, it is by far the deadliest substance that can be mined in this stratum.

Pyrestone is the one building material that allows a permanent structure to be formed in the land of fire and ash. Without it, putting one brick on top of another and expecting it to be there the next day would be all but impossible. Resistant to heat and seemingly immune to the degrading power of ash, even at the deeper layers where it becomes more potent, Pyrestone is the bedrock of civilised existence within the world of demons.

Excerpt from 'The third stratum: a primer' by Mallin the educator.

As the vast army of the Colony flowed into the area around Orpule they set to work like a well-oiled machine. Soldiers peeled off the line and started to set up patrols and a perimeter even as the carvers began construction of a vast project. It was fascinating to watch it happen, sitting up on my rock it almost reminded of looking at timelapse videos of ants at work. A flurry of activity, dirt getting moved around with thousands of little bodies rushing here and there. The main difference in this instance, of course, is that every being I see is a fully sentient creature. There's no wasted movement, no back and forth, just a clean execution of a previously agreed on plan that was carefully considered.

In ten minutes, tons of rock has been shifted, clearing the ground for what is to come. The vast field of plains around the pillar that supports the ceiling so far above our heads is effectively surrounded, teams of ants having formed a living wall around the city. Still, the vast concentration of the army remains here, close to me, feverishly building in a long line that extends from my position all the way to the base of the pillar. Fifty minutes later and by now even the demons should have been able to work out what is happening. The beginnings of a vast rampart are taking shape the likes of which this stratum may have never seen before. Several kilometres long it will reach from the ground all the way up to the lip of the plate on which the demon city sits. A truly ludicrous undertaking, but one that the Colony will attempt to execute even so. Huge trails of soldiers and scouts have formed in all directions, hauling hundreds of tons of stone every minute back to the construction site where mages and carvers broke it down and fused it into the ever-growing ramp.

It was glorious, it was mad, and it was amazing all at once.

This is the power of the Colony when they bring their numbers to bear. This is what forty thousand of us can do when we work together in harmony. In a year there might be a million of us, or even more. What wonders will we be able to accomplish at that time? I can't help but get shivers as I think about it.

But now's not the time for sitting around on my backside daydreaming! Eventually the city is going to start to retaliating, firing spells and dropping rocks on us as we build! At that time, I need to be on the frontlines, ready for action, which means I need to be mutating and resting my mind now, to ensure peak performance when the battle is at its peak!

No longer willing to stuff around and watch others work (think of my reputation!) I rush down into the resting chamber in which my group is already slumbering and prepare to mutate. This mainly involves making sure that nobody can see me, and I'll be protected during 'itch time'.

With this job done, it's time to weigh my gains. How many points to I have to work with?

Five hundred and forty-seven. Not bad for a week's work, especially considering the fact I've been sharing the food with a host of tier sixes (and a seven). It's enough for me to take three of my organs.. aaaalmost four of them, from +25 to +30.

Which of the lucky body parts will it be?