Ignoring the still-blushing Einstein across me, I dance my hand along the sheet of paper, making another set of blueprints.

"Your designed has given me some ideas, Einstein." I said, finishing a sketch for what would become the first generation of IFV. "That 57 autocannon of yours will be a fine addition to this upcoming project."

Motioning Einstein to come closer, we both start working and throwing out ideas for the new IFV design.

"Infantry fighting vehicle, another new concept coming from you. What are the requirements?" Einstein asked.

I then iterate my needs for the vehicle with crossed arms.

1. Utilizing the parts and techniques from the Leopard. The new IFV must be modular in design and weigh no more than 20 tons in its heaviest configuration.
2. It must be able to carry eight soldiers.
3. It must be amphibious.
4. The infantry must be able to fight from within the vehicle or dismounted.
5. Protection from nuclear, biological, and chemical weapons.

Hearing what I listed, Einstein scrunches her eyebrows.

"Are you sure you're not making another tank?"

I just shrug.

"We're breaking new ground in military doctrine here, can't fret over pre-established common sense. Trust me, after five years, you will see that our military will be undefeatable."

Nodding, Einstein says. "I will hold your words for that."

After the short discussion, we dive into the designing phase of the IFV. With two of the most brilliant minds working together, we soon come up with the perfect blueprint.

Being dubbed the Puma by Einstein, the new IFV shares an astonishingly 70% parts commonality with the Leopard. It also checks all the previously established requirements. Being modular, roomy, amphibious, and extremely survivable. Using the same powerplant, transmission, and suspension as the Leopard, the Puma can ferry a fully-armed squad with unprecedented speed and comfort. Such a vehicle is the ultimate representation of the Belka Blitzkrieg doctrine.

In its stock configuration, the Puma has a mass of 14.6 tons and is equipped with a 30mm autocannon and a coaxial MG-34 (placeholder). The Puma has a crew of 3+8 with the driver sitting lower down in the hull while the commander and gunner man the turret. The 8 passengers are situated in a separate compartment behind the turret with a large ramp door. On top of the troop compartment are four hatches, allowing the soldiers inside to turn out and engage nearby enemy infantry.

There are currently three loadouts for the Puma to choose from:

One is loadout Class A with notable features being the belt-fed 30mm MK 103, the autocannon design is one of the seven making up the Gepard's Gatling with 400 rounds. The basic armor can resist direct hits from 13.2mm Hotchkiss used by Ustio and the powerplant is downgraded to a diesel engine, outputting 550 horsepower. Ammunition for the 30mm includes APFSDS and HE-VT.

The second is loadout Class B, weighing 17.2 tons. This is the up-armored and up-armed version of the Puma. Using the same 57mm L/77 MK 57 autocannon as the Gepard SPAAG, minus the radar system. It can swap the 57mm out for the 30mm MK 103. The all-around armor of the Puma is graded for medium-caliber and shaped-charge projectiles, while the roof armor is able to withstand artillery or mortar bomblets. This version and Class C have the same powerplant as the Leopard MBT.

Last, but not least, is loadout Class C. This is the weirdest and deadliest version of the Puma. Forgoing the troop compartment, this version used the Leopard 105mm with its autoloader while having the same armor value as Class B. Weighing at 18.4 tons, this is not just a Puma anymore, but a whole different vehicle altogether. I would argue that we come up with a different name for this one but Einstein disagrees.

All loadouts can be mix-and-mash with each other depending on a unit's field requirement. With the armor being the easiest to install and replace.

The whole vehicle is protected against heavy blast mines (up to 10 kg) and projectile charges from below, while still retaining 450 mm ground clearance. Almost all equipment within the cabin, including the seats, has no direct contact with the floor, which adds to crew and technical safety. All cabin roof hatches are of the side-slide type, which makes them easier to open manually, even when they are obstructed by debris.

Finally, the Puma is completely amphibious and moves with the help of two water jets that allow it to reach a speed of 10–12 km/h depending on the state of the currents. To increase the buoyancy, wheels are equipped with airtight chambers and powerful water pumps; extracting water from the lower chassis. The vehicle is sea-worthy and can cross water obstacles without preparation in a sea state of up to 3. While waterborne, the Puma retains the capability of firing even the 57mm.

Once I and Einstein are done giving a final look at the design, the pale blue hair woman exclaim. "What the fuck did we just come up with?"

Shaking her head with a hand massaging her temple, Einstein continues.

"I swear, just this thing alone is enough to bring the fight to Erusea soil."

I snicker, giving her a piece of my mind. "Well, that was the intention."

Rolling her eyes, Einstein changes the subject. "I don't think we will need any more adjustments and can just ship these straight to the prototype stage. Well, we will need to swap out the MG-34 on these designs later though."

"We have all the time in the world right now." I commented with a hidden meaning, putting the Puma blueprints away. "Best we make good use of it."

Einstein helps me with the task while asking. "Speaking of, how do you want to use these things?"

I explain with a smile as I slide the last of the Puma blueprints into a case. "Well, Class A, believe it or not, wasn't made for our military per se."

"I can figure that just by the downgrade in overall capability." Einstein interjected.

"Smart girl, want a cookie?" I jested the usually stoic Doctor.

Sighing, Einstein responds. "Back to the point please."

"You're no fun, loosen up a little." I pat her shoulder before saying. "Anyway, Class A was made to be supplied to our allies in the future, after we have outfitted our armed forces with Class B and C. Even if it's a downgrade, Class A is capable of outmatching anything that's not a heavy tank, if employed correctly. As for Class B and C, they, alongside the Leopard, will be the backbone of our military. Class B will secure the flanks of our MBT with their Grenadiers while the Leopard takes on the heavy hitters of the enemy. Class C, on the other hand, will fill in the niche roles of a tank destroyer, scouting, and hit-and-run with its exceptional speed and firepower. And with them being amphibious, we can create a new branch of our military, the Marine. Though with them being this light, I've some plans to outfit the Air Force with these bad boys."

With a twitching eye, Einstein asks. "Do I even want to know about your crazy idea? I swear, Dreamer has been putting me through the wringer with her plans, not you too, please."

I chuckle with a hand over my mouth. "No promise." Pulling out another blank sheet of paper, I then say. "The day is still long, let's continue."

"Something not too ridiculous, if you can." Einstein pleaded.

Complying with her request, I say. "Sure, how about infantry stuff this time? Still need to improve our Grenadiers' gears."

Einstein adds. "Mobius and Dreamer have been working on improving our soldier's survivability so I don't see a need for us to intervene just yet."

"So this only leaves firepower for us to improve on. That decides it then." I concluded.

Einstein pitches in. "I have a few ideas." She then moves on to design an entire family tree of weapons. It takes some time but I watch on with interest, leaving the woman in her own element. Not gonna lie, her focus and commitment to her work are a beauty of their own.

I let Einstein adds the finishing touch to her designs before commenting on the results.

"Masterfully done. I see that you've been cooking these up for quite a while at least."

Einstein jumps up in surprise, forgetting for a moment that I am right next to her. The Doctor's action of scratching her cheek embarrassingly is cute. "Well... Studying how firearms work mechanically is a fun pastime for me, and knowing how to improve on them is the side benefit of that. Your endorsement has allowed me some leeways to come up with these designs."

I nod with a small smile. "Then tell me your thoughts."

Einstein returns to her professional work ethic before explaining.

"This is a rifle but not just any rifle, it's a select-fire rifle that's chambered in 8mm Mauser, operating on the principle of roller-delayed blowback. Temporarily dubbed the G1, this rifle is a modular weapon system. Its butt-stock, fore-stock, and pistol-grip/fire-control assembly may be changed at will in a variety of configurations. While the user is able to mount a magnified optic and additional accessories on the gun. Simple push-pins hold the components in place and removing them will allow the user to remove and replace parts rapidly.

The G1 is hammer-fired and has an ambidextrous trigger mechanism with a 3-position fire selector switch: Safe, Semi, and Full-auto. It has drum sights with range and windage adjustment and the receiver has a rail system to mount optics.  Its barrel is free-floated from the stock and has polygonal rifling. The barrel chamber is fluted with twelve flutes, which assists in the initial extraction of a spent cartridge casing. At the front of the rifle is another set of rails for attachments and you can exchange the muzzle device for something else.

G1 comes with a brass deflector and the option to be fitted for left-handed users. Its feeding system is optimized for 20-round double-stacked straight box magazines, a 50-round drum magazine, or a 100-round drum magazine.

There are currently a few variants that I've come up with:

1. The basic G1 is suitable for standard Grenadiers and capable of firing rifle grenades. 500–600 rounds/min rate of fire.
2. SG1, the sharp-shooting rifle, has a contoured barrel to help with harmonic stabilization and consistent whip but remains free-floating. The stock is composite and has a high degree of adjustment. It is adjustable for length and includes a pivoting butt cap and a vertically-adjustable cheekpiece. The forend is fitted with a T-way rail for a sling swivel or tripod. Its rail system is long enough to hold long-range optics while the charging lever is modified in a way to not interfere with them.
3. MG1, a squad machine gun, has a free-floating, heavy, quick-change barrel and is capable of mounting a muzzle device. The drum sights are adjustable and the machine gun is capable of mounting medium-range optics. This machine gun is made specifically to handle intense firing using 100-round magazines at  800 rounds/min.
4. MP1, a G1 downscaled to a submachine gun chambered in 9x25 with 32-round of ammo. The rate of fire sits at 800 rounds/min."

Einstein then takes a breather after that long explanation. "So, what do you think?"

I clap my hands, praising. "It's a great design! If we equip our military with your guns, any and all member of the armed forces can take on an enemy thrice their number!"

Blushing at the high praise, Einstein can only mutter a short thanks. I smile before pointing out a few improvements to her design. That and pitching in some of my own ideas for the G1 variants. Stuff-like integral suppressed designs and usage of a special gas system that lower the muzzle velocity to subsonic. These are ideal for special operation groups to lay out the pain unnoticed.

Einstein soaks up the information like a sponge, her eyes marveling at the design of the suppressor. "If we install suppressor on the SG1, assassination will be made a whole lot easier."

I smirk. "You don't say."

After finalizing the G1 and a few knit-knacks for the Grenadiers, we move on to the hard hitters used by the standard infantryman. And at the end of the day, we've designed a few more weapon systems.

A Panzerfaust, is a compact, lightweight, shoulder-fired, unguided anti-tank or anti-bunker rocket launcher. It consists of a disposable canister with a 110-mm warhead and a reusable firing and sighting device.

A shotgun, S-12G, features a bottom-loading, side-ejecting receiver, and a tubular magazine holding 7+1 12 gauge rounds under the barrel.

A modular, multi-caliber sniper rifle, chambered in 8mm Mauser, 14.5x114mm, 20x82mm, or 20x120mm. The larger caliber is intended for anti-material, deployment against targets including parked aircraft, vehicles, telecommunication masts, gun emplacements, bunkers, and personnel, using a range of specialized projectiles. As with other weapons of this type, it can also be used for counter-sniping and ordnance disposal.

Last but not least is the MG-35, a replacement for the MG-34 general-purpose machine gun. Even though the MG-34 is a new arrival in the armed force, it has its own limitations. the MG-35 aims to overcome them and be comparable to the upcoming MG1 made by Einstein. The MG-35 will fire 8mm Mausers from an open bolt and use a long-stroke gas piston to cycle the conventional rotary bolt action. It's modular and has a quick-change barrel much like the MG1 but is more suitable to be mounted on vehicles as it's belt-fed.  Though it's very capable of fulfilling the role of a squad medium machine gun with its 120-round belt box.

Very pleased with a profitable day, Einstein and I pack up the mess made on the workstation. Thankfully, we managed to end the day early than the last time, mostly to the fact that I've been cheating with my Time power. As the last of our papers and blueprints are safely stowed in a strong box, Einstein turns around to address me.

"Well, that was fun." She yawns before saying. "If you don't mind, want to go and head to the cantina? I really want a cup of coffee right now."

I shrug. "Sure, we can get something light to eat before I need to head back. Though I'm not sure Erika will be available at that time, she needs to go pick up Ningyo, I think."

"Then I will drive you back, just don't hope for a limo." She offered,

"Knowing you, Einstein, your car would be one of the comfy kind, not a luxurious one." Turning to look at her with a small smile, I take up her offer. "And I like it that way."

We both chuckle before making our way to deposit the box at Dreamer's office. She will help us get the designs ship to a factory under the Royal Family's control. As for us, we enjoy a nice warm dinner together before calling it a night. Unexpectedly, we both grow closer after a period of working harmoniously together.