What is it that makes a good AC? What is it that defines an excellent machine? How did Core Theory influence the designs, both for oneself and one's enemy?
As one might expect from such wide-ranged questions, the answers are complicated.
The term 'Core Theory', for starters, isn't actually a single defined term. Core Theory refers to several different concepts depending on whether you're talking about Augmentations, Mech Design, or Warfare.
Core Theory, in reference to Augmentations, was a relatively simple notion. Unaugmented Humans were, in all but the absolutely most extraordinary cases, simply worse than Augmented Humans on the field. It was right there in the name: Augmented Humans.
One expects, then, that Augmented Humans would be the centrepieces of the field, the points which all other things revolve around, the 'Core'. Hence, Core Theory.
Core Theory, in reference to Mech Design, was quite a bit different. It started out as something along the lines of 'Augmented Humans need better machines to make better use of their talents according to Core Theory', but it ultimately ended up pivoting to a specific kind of mechanical designing in mechs; the Core, the Frames, and the Units.
See, the best way to get the most out of Augmented pilots is to build a machine that translates closely to what they're already expecting. It's a simple jump for the brain to go from moving one's own arm to moving the arm of a mech, but a bit bigger to make the jump from turning a hand to twisting a turret. It wasn't impossible of course, the mere existence of Quadrupedal and Tank 'Legs' showed that.
In those early days of mech design, building the humanoid frame to take advantage of the low learning and translation requirements was the goal. Thus, you get mechs with chests, heads, legs, and arms. This constitutes the 'Frame' of a mech, usually divided into exactly those four categories in modern classifications.
'Units', in turn, referred to what a mech was equipped with. There had been some strange designs in the past, but in the modern day, these Units were categorised under the two Arms and two Back mounts.
The trick is that every pilot wanted something different. Pilot A might enjoy a massive tank carrying more explosives than a third world country, but Pilot B liked having a mech intended to cosplay a particularly vicious fairy out to claim your bones.
Since it would naturally be economically ruinous to develop entire fleets of different mech types solely for single pilots, most instead turned to a set of standardised parts and connections. Frames and Units were given adapters, and they were built with the expectation of being plug-and-play. Someone, at some point, was going to rip the arms off of one AC and superglue them to the AC of a different group, and that versatility and compatibility was a requirement for any Pilot to even consider using your mechs.
This design philosophy came to be referenced as 'Core Theory'; the central core through which everything else could attach.
Eventually, it would come to be termed 'Armored Core'.
Core Theory, in reference to Warfare, was a term that itself referenced both of the other definitions. See, the results of Augmented Pilots and augmented machines were nothing short of spectacular. Expensive, yes. Difficult to replace, yes. Worth it? Every penny.
It actually started out being called Military Core Theory, I'll note. I'll also note that when it came to warfare, Core Theory was informed by the earliest days of AC-focused combat; IE: Close range, high speed, very dangerous, where single staggers and system faults could and would decide the fate of things. Under Military Core Theory, ACs belonged in the melee; fighting outside of a few hundred metres was just... not effective.
For the most part, that was right. An attentive and alert pilot would handily either dodge or aim-dodge any attack that came from further than that.
So with all of that in mind, what did it mean for my Firekeepers?
Well, there were a few additional factors for me to consider. I could handily nix the problem of 'money', but I couldn't quite nix the problem of resources just yet. I unfortunately did not have access to the full production of an entire planet covered in Grids and then a star system outside of that like the Rubicon Research Institute used to, so I couldn't just throw resources at the wall until something stuck.
I didn't need to, though. They'd already done that work for me. I just needed to iterate from there.
Another factor: I couldn't make use of the more truly exotic materials that a full nucleosynthesis plant would have gotten me, but you'd be surprised by how little that narrows the options down when you're scavenging from a Grid and you've already got Coral on hand.
One final consideration: My Firekeepers were not intended to operate alone, unlike most ACs. Their lives were a little bit too precious to me, and they didn't have the raw skill they needed to engage the PCA's forces on their lonesome yet.
So it was that I began a new project.
IB-C04.
It was, for the moment, a temporary designation. IB for IBIS, C for Controlled, and 04 for project number.
I would be using IBIS-derived technologies here, so it was deserving of that title. Controlled was naturally rather obvious; it had pilots rather than an AI. As for the project number, well, that was just bookkeeping.
IB-C01 had been just a test, and petered out before it could produce anything of actual use. IB-C02 had started with the goal of merging IBIS technologies with traditional Armored Cores, but it also hadn't reached production stages.
IB-C03, obviously, had been Nagai's best efforts at containing his feared Collapse.
IB-C04 was a project for exploring the possibilities of symbiosis between Humans and Coral. I was actually taking the data from C01 and C02 more than I was from C03; the HAL was incredible but it was also very much a solo machine focused on individual quality, disregarding any resource or monetary concerns.
It's... decidedly odd body shape pointed that one out. The extended back and control pieces were awkward to work with.
IB-C04's preliminary designs had a much more normal humanoid shape. Aesthetically, it had more in common with the IB-07 SOL 644 than it did with the IB-C03 HAL 826; it was symmetrical, it had the radiating surfaces, but it differed by being visually 'simpler', with larger plate and fewer mechanical gribblies; a result of the fact that it was significantly simpler. It didn't have to transform into a jet, after all.
The sole exception to that was the head, which, while it shared the visual effect of the Coral underlay, was closer to the HAL's head. A bit more elongated, and also with a pair of backwards sweeping antenna rather than the forward-facing one of the HAL and the otherwise 'flat' face of the SOL.
It was a firmly middleweight mech, but that was not the same as saying it was a middle of the line mech. It was packed to the brim with IBIS technology and its performance was significantly better than what most would expect. Superconductor cabling lines, direct Booster-adjacent capacitor feeds, electromagnetic gearing, Coral-augmented particle feeds - it was, under the hood, a hell of a machine.
The cost for such high performance would be in repairs and maintenance. One would be looking at roughly three times the price of the next costliest AC to repair, but well, I didn't care about that.
I already had the setup for construction and repairs. Their lives, and the experience they would gain, weren't things that could just be replaced.
Aside from that, the internal components were mostly IB-C03 components at the moment. I had a few ideas in that department, but I was still in the prototyping stages there. I did hope they panned out.
If it all came together and IB-C04 ultimately led to a full AC, I'd have to find a name for it. At the moment, all the Frame components are just listed as IB-C04(H/C/L/A).
Of course, all that was just the Frame. I hadn't even mentioned the Units.
I could not even begin to count the number of weapon designs floating around in my mind. A lot of them weren't even mine; the RRI were, after all, a bunch of mad scientists at the best of times. The difficulty was always in making them into something usable, after all.
Most of them... weren't, so far. As a matter of fact, only two weapons were now available under the project. The first was a upscaled laser rifle, heavier than most but also equipped with solid-state cooling systems for rapid heat dispersal. Unlike most AC energy weapons, this one didn't need external coolant supplies, so it was good to go theoretically forever, and practically much longer than it would ever spend on a battlefield. Its energy output relative to its size wasn't the best, but it would still take some chunks out of most anything. Especially if you bothered to charge the thing...
The other was a Coral Oscillator. A melee weapon that functioned by manipulating Coral, inducing temporary Surges while launching it at the enemy. This Oscillator, which was currently being called the CO-SD1, was a bit smaller than the Oscillator developed in the IB-C03 program, the WLT 101. Where the WLT 101 could be called a blade, the CO-SD1 would be more of a dagger. It was dangerous, of course, it was still a Coral Oscillator, it just served in a different role.
In the future I'd be able to do a bit more for my Firekeepers, but right now... that was pretty much all I had.
I had divided them all into four groups, five in each of them. They all favoured different weapon types and different loadouts, but I'd done my best to split them, approximately, by role.
For each team: One support, one melee, one scout, and two ranged. In terms of actual equipment, it wasn't too different with the current lack of designs, but in general: Support would be carrying long ranged weapons and missiles; the melee would be carrying a short ranged weapon, a melee weapon, a shield, and a missile launcher; the scout had two short ranged weapons, a shield, and lightweight Back Units; and the ranged would be carrying a pair of middle ranged rifles, with some more missiles because who doesn't like missiles?
Necessary? No, not really. I could honestly, reasonably expect that any of them alone could handle what I was sending their entire squads to do.
The point, however, wasn't about the costs of it at the moment. What we wanted to do was pull attention away from the RLF.
To do that, I was sending the Firekeepers to four different locations. They were going to be hitting a bunch of targets throughout northeastern Belius.
The goal, primarily, was the total destruction of local Doser forces. Simple enough for ACs, with no expected further issues. The locals had a lot of extra MTs due to the PCA's shenanigans resulting in a group of them 'mysteriously being abandoned and then found by unrelated third parties'. The PCA did this whenever they needed a deniable way to make the RLF extend in some direction so that they could then 'respond to the use of force by terrorists'.
It's not like the RLF was going to abandon the civilians, after all. They weren't the PCA.
Our goal was to pre-empt the matter entirely. We wouldn't be making contact with anybody around. Hit the Dosers, take the Coral, grab as much intel as we could get, then get out. Seria would pass the info to the RLF upper echelons, and we'd fade back into the shadows for a bit before preparing something else.
It would only be the start of things.