Warning: Beginning stages of vast improvements and suggestions in weapons, tactics and equipment. Most specifically suggestions on Panzerfaust and Rockets. It makes sense in context, but shows how far someone will go to accomplish their goals. Read at your own risk.

"Are you going after them?" Astrid calmly inquired. "After my brother who is weeding out the diseased branches of humanity here?"

Erwin looked down at the blank expression on the child and frowned at how her eyes showed her true feelings. Her golden eyes burned with the rage, disquiet and fierce devotion and protection for her beloved brothers. The contrast between her burning gaze and the emotionless doll-like quality of the rest of her face was unsettling. The flicker of satisfaction in her eyes at sensing his own discomfort, amused the young man.

"As far as I am concerned, that is the military police's job and knowing them they will ignore it."

Astrid nodded her head, pleased with this information. "Good. I, we, made a deal each other that if we lost sense of ourselves then we would only let the remaining sane individuals to kill them. I care not for honor or oaths, it is a foolish chain that suppresses ones true potential, but I always hold my end of deals and covenants I make."

Her words were spoken so coldly and she seemed so sure in herself that Erwin didn't doubt what she had to say.

"You have killed before?" Erwin asked to clarify things.

"Yes. Humans, animals, a few failed candidates and three or four titans. Forgot how many of theose fuckers we were up against during our own preliminary test run."

Her words were spoken in a matter of fact way like she was just recounting what she saw happened and had no personal connection to said deaths.

This didn't bother Erwin as much as it should have. Instead he focused on how the small girl stood at attention like a soldier delivering a report. Her gaze did not wander away from facing forward or toward himself which was rare even for older children.

Grisha who was silent unto now asked, "Did you feel anything when you killed?"

Astrid sighed, a small amount of regret and annoyance shining through the still mask she had on. "Despite my condition doctor I have every emotion that a normal human has. Hell, at times they are even stronger which both helps and hinders me." She shook her head to clear it. "At the time I couldn't afford to see my targets as anything other than obstacles. They were going to threaten my loved ones if I didn't get rid of them first."

Erwin closed his eyes in thought. Most of the papers that remained in that hellish place and were undamaged revealed how the trio worked in the few field trials and exercises among the public they were given. The vast majority of the remaining paperwork was observations on different levels of society within the walls written in childish handwriting.

"What's the difference between warriors and soldiers?"

Erwin saw the mask of indifference fall off her face and knew it was Astrid who wrote at least one article.

"Organisation. Warriors fight as individuals, even when there are a bunch of them together. They may be good at it, but everything they are involves fighting their opponents independently. Soldiers, by contrast, work and fight together. They can be individually as capable as any warrior but their effectiveness is far greater, because they co-operate and complement each other. This subtle difference explains why humanity is losing the fight against the titans: It's because they're complete fucking idiots." Astrid lowered her head in a mildly mocking manner. "Sir."

This little kid had guts to be that blunt to his face but she was right. As much as Erwin hated to admit it, the military system wasn't working at all.

He would have be lying if he wasn't curious on what she truly thought.

Surreal wouldn't even begin to cover how the exchange went for the poor doctor watching them. It started off as almost humoring the young girl and ended with plans and weapons schematics far above this regions current technology level.

Erwin watched the girl lean her back against the farthest way, her right heel tapping the wall in thought. Her eyes darted back and forth, no doubt checking their surroundings for anyone listening in.

When she spoke again, it was very formal and respectful. "You can both interrupt me to ask questions. Otherwise, I will be concentrating first on the failure of the military system, starting with strategy and tactics."

Neither one spoke up, so the girl cruelly attacked everything she could.

"Let's start with the basics: You fail at this profession! You have a shitty strategy that boils down to 'sit behind our walls and pray that the titans go away'. There is no Deity watching over you idiotic twerps, so you better wise up and fast if you want to live. The stalemate you guys are in will only last until the titans find some way to get at the humans inside these freaking walls. What then?! What's your big plan?"

Grisha interrupted the young child's explanation by calmly pointing out how unlikely such a event will be. The doctor was shut down immediately.

"In the year 845, not only will we lose this district but the entire Wall Maria will be compromised due to titans breaking into your sanctuary. Food will be scarce within a year of the attack and about 200,000 to 250,000 individuals will be sent into Titan territory in an attempt to get back regions." Astrid scoffed like that thought offended her greatly. "Which is really another way of removing excess stress on resources."

"How do you know this?! It should be impossible to know the future!"

Astrid lifted her head and leveled both men with eyes that they were far older and wiser than they were used to. Haunted by knowledge or loss, it didn't stop them from seeing the sharpness and reluctant desire to help them. They were the eyes of someone who anticipated the very worse case scenario in everything and survived because of it.

Just as quickly, the old eyes were replaced by a childish joy, making both men feel like they witnessed something they should not have seen.

"It's simple for those who are like me to see and even predict events. No, what we should be more focused on is my Kind. They are far worse than any Titan, more corrupt than Marley," Astrid paused at seeing the doctor stiffened and she looked at him and silently promised to talk to him later, "more powerful than anything this world has ever seen, and each one of them, aside from myself, views everything as playthings and expendable. They can even rip apart reality, and trust me, it's not fun."

Astrid looked down, obviously regretting bringing this up. "Most are far weaker than me on a bad day, but I haven't used my powers often in a very long time. Thankfully, the others are generally limited in what they can change, alter, create or accomplish. Personally, I believe it is either Ziv or Malika who created the Titans originally given their love of deals and turning humans into body horrors and monsters."

This was absolute insanity. And yet...

"You will fight against the titans and this Kind of yours for humanity?"

"Maybe."

Maybe? But wasn't Astrid suggesting she would aid us?

"While I have a vastly more affectionate attitude to the rest of creation then my kind, I am a still very much the same as they. Also, I tend not to think much of humanity as a whole." Her eyes flashed, green mixing with the gold but it vanished after a second. "However, I also will not see your race crumble before me when I can stop it. I will help you out of my volition, but there are parts you might not like in both my plans and what I might do."

Neither one knew what to make of this development, so they simply let her continue on her original discussion.

"You all get slaughtered wholesale for no appreciable gain whenever you attempt those piss poor operations tasks. And tactically, your method of dealing with titans is so far from effective that I don't even know what to say. The equipment, weapons, training… everything is predicated around getting someone with a sword up to the titan's neck so they can slice it open. Words fail to express how indescribably fucking stupid this is. What makes this even more infuriating is that humanity has millennia of experience of how to deal with similar tactical problems. It's a part of your fucking DNA! You are giving away every possible advantage you could have, and transferring them to your enemy. This is the sort of insane idea that could only be come up with by someone who is fixated on individual prowess and achievement at the expense of all else. In other words their strategy, operations, and tactics all look like they were created by warriors. And that's one of the main reasons why I don't think you have a single soldier in the shitty hellhole you call home."

Erwin opened his mouth to speak but was blocked by the next topic of: Supporting Arms.

"The other main reason is the lack of thought that has been put into what you do if you're not swinging a sword at a titan. There are three arms of service – the Survey Corps, which does reconnaissance and light-infantry tasks; the Garrison Corps, which maintains and defends the walls; and the Military Police, who act as a sort of police force and praetorian guard but fuck those guys. There don't appear to be any organisational levels between that and the squad that you're assigned to, which must make assigning tasks an absolute nightmare for commanders. Naturally, there are some truly bizarre oversights being made."

"Bizarre like what," Grisha wondered aloud.

"The walls for one," replied Astrid with a shake of her head. "I'm ignoring how it was truly made and pointing out flaws as if it was designed by engineers." She crossed her arms and looked to the side. "See, the walls are built as fortifications. Their entire job is to prevent titans getting in and other than the fact they will soon fail, there was nothing altered to help strike the Titans from cover. Hell, there are no secondary fortifications in case a breach was made in the wall nor are there additional walls as spokes to limit the amount of territory lost in the event of said breach. If I didn't know any better, I would think the people inside the Walls were sacrifical lambs. The oppression of all knowledge about the outside world certainly makes this place feel one bad day away from complete dystopia."

Despite how mocking Astrid's last sentences were, both men knew what she was getting at.

The girl continued on her rant. "The 3-d manoeuvre device that everyone uses requires incredible athleticism and conveniently placed trees or buildings to swing from, but that isn't viewed as a drawback. Blood anime and manga logic. You idiots will go riding at full speed through territory controlled by titans and firing off smoke signals like they were going out of style, but this is an massive improvement on previous methods."

She paused to look at the person who was designing the tactic and laughed sheepishly. Astrid went back to explaining her views. "No-one appears to have even thought of using different weapons or gear, co-operative tactics, reconnaissance, communications, terrain features, engineering or artillery or in fact anything other than swinging up to a titan's neck like a bloody monkey and slicing it with a sword. The technical level of human society here approximates the mid-1800s in my original reality: you've had your industrial revolution, but haven't quite got to mechanising everything. Even so there are plenty of things that would make a difference."

"So you came from another world," Erwin stated with a conflicted expression. He was torn between believing her words at face value and denying it. Even when she nodded her head once in confirmation, he couldn't shake his hesitance.

"My reality was theirs as well. Five years ago, they conducted some sort of ritual that sacrificed reality and that universe in exchange for taking everyone with that power to other dimensions and time periods. Even I could not avoid it." Hurt crossed her eyes but was pushed aside by pity. "Due to an offer my greed and addictions could not refuse, I am forced to mend the damage my Kind will cause and better worlds if possible." Briefly, Astrid closed her eyes as if in a short prayer. "The original owner of this body died when she was just shy of a year old. I was compatible with her body and because it was a rush job, I didn't have time to look for a more suitable body. The trauma of being forced into her tiny body, the rush of memories I was experiencing from two different people and the rush of new yet familiar experiences suppressed my original self until recently." Astrid frowned as she ripped her arms tightly. "I am not eager to see what I experienced during this gap of time."

Erwin couldn't blame her after seeing the procedure rooms and the holding cells. "What else?"

Astrid smiled a little in thanks. "As someone who was professionally a soldier for a time before moving to mercenary and other less noble occupations, what angered me most about the local military was the indescribably poor organisation and complete lack of professionalism on display. This leads to suicidal tactics, lousy planning, and a general failure to be effective. Lucky for you guys, I have some ideas."

The grin on Astrid's face seemed to spread from ear to ear and was mischievous and knowing. "While there are those who know quite a bit about titans, coming up with a strategy for others will be difficult. It needs two parts – one in which they hold off the titans and learn more about them, and one in which their source is attacked once it's been identified. Then, and only then will we defeat the titans by learning where they come from, and then blowing the fucking place sky-high.

Grisha eyed the girl with suspicion. "You know where that is, don't you?"

Her face blanked for a second before her grin returned darker and more twisted than ever before. "Of course! Not that it would help you guys anytime soon. I already have my own plans on dealing with those nuisances."

Erwin filed the interaction between the two away to investigate at a better time. "From your experience, what do you suggest for the military branches?"

Astrid ignored his stress on experience and answered his inquiry. "All the military branches need some organisational levels between "squad" and "corps". Making use of humanity's superior numbers requires better organisation, so the basic operational group should be five squads of twelve soldiers assigned together more or less permanently. This is an ideal size but given how rare people actually join the Survey Corps of their free will, we will be working on five squads of six to eight soldiers. Less if we absolutely must. Although every squad should have a scout or two in it, one squad will be specialised in that role. Another squad will specialise in the care and feeding of the weapons I'll be mentioning later. The other three will be general-purpose 'tactical' squads. Having them permanently assigned to the same unit will give everyone a chance to train and get used to working together, and is a manageable number to keep under control once the fighting starts."

Astrid stopped to see if they had any questions so far then continued. "Both the Survey Corps and Garrison Corps are going to be busy and efficient for once. The Garrison Corps needs to not only take care of any titans that wander up to the walls, but also find ways to defend outposts outside them. This is going to mean developing specialists in engineering and artillery. The Survey Corps, meanwhile, will have to provide advance warning of titans and also start conducting longer-range patrols to find out where they're coming from. Also, I suggest adding on research facilities, intelligence programs and the like to the Survey Corps in order to further human and world interests. Not only will this give you more credibility among the mindless sheep, but once this whole Titan business is over with, you have prospective career choices ahead of you."

"You didn't mention the military police," Grisha pointed out with crossed arms.

Astrid lifted her middle fingers and positioned them in the direction of their headquarters. Seeing identical blank faces, she told them what that meant. " It means fuck you." She rubbed behind her neck to ease a slight pain there. "Why would I want to help those corrupt bastards anyway? Waste of potential. Besides, they won't have much power or status soon enough."

Erwin heaved a sigh of relief that they didn't have to fear her turning to join them. "Tactics," he ordered and the girl snapped into a stance that was similar to the ones he was used to seeing. Judging by the scowl on her face, Astrid fell into this position out of an old habit than choice.

"For the most part, the tactics of swinging around and waving swords will be lessened due to the appalling casualty rate and lack of consistent results. I suggest we remember the basic phases of a battle: find the enemy, fix them in position, and then destroy them. Since we will hopefully have these units I mentioned earlier, let's get as many of their members as possible engaging each titan. To find the titans, we need scouts who can pass back information without getting eaten."

"Trap them you mean," Erwin muttered.

Astrid nodded her head once. "To fix a titan, we need some way of keeping it in the same place long enough to do invoke the trope of no kill like overkill. Luring it into bad terrain might help but it can't be relied upon since it can hurt our troops just as much. We know that titans' eyes, muscles, and tendons are just as vulnerable as those on a human. They also can't easily break the cables used by the manoeuvre devices." She took in a calming breath. "Which brings us to the third phase, destruction. The only way to kill a titan is by destroying the nape of its neck, but you don't have to do that with a sword. Enough damage will do the trick just as well. So there's the outline of our tactics against titans: Find them, manoeuvre them into position, and then engage them from multiple sources. First to disable them, then to kill."

"What about equipment? Changing tactics so drastically must mean you have new ideas for tools and weapons."

Astrid nodded her head. "I do but for the most part I, and those I can trust to not abuse or sell the secrets to making them, will be producing the items." She sighed at seeing their curious looks. "What I am offering will be customized to only work on titans and other non-humans but it is still close enough to giving iron age tool using people a nuclear weapon and letting them play with it. You will see what I mean soon enough."

Erwin motioned for her to move on.

"The three-dimensional manoeuvre device has flaws despite it's usefulness," Astrid began with a small smirk. "It requires a lot of ability to use as well as conveniently placed terrain, damn anime laws, and only lasts about 20 minutes before the gas cylinders need changing. But it does give users much more mobility, which is important. So we'll keep it, but add an item for anyone using it: a fucking helmet. The real question is how to disable the titans for long enough to do something more than tickling the fucker. A single shot variation of the harpoon cannons will be best. That way everyone can carry one or two, and an onslaught of those beauties will still cause massive problems." She paused and looked skittish, almost afraid before asking, "Permission to show you both something?"

The men looked at each other warily but they consents after a few minutes of consideration. Strange shadows encased the room before darkness swallowed there vision. Just as quickly as it occurred their sight was returned and what they saw was unusual.

They were in the field outside the Walls and the girl was missing. In place of the girl was a very tall young woman somewhere in her mid to late twenties dressed in black leather armor. She was tanned from fighting outside and traveling but that only made her greenish-gold eyes and platinum blonde hair stand out more. A scar an inch or two from some type of claw crossed the corner of her dark lips which were tilted in a mocking grin that was all too familiar at this point.

"Astrid?"

The woman nodded and held her arms out as if ready for something to fall into them. And something did indeed.

It was a projectile of some sort and resembled a large oversized head on a long hollow tube, which was no doubt filled with gun powder which acted as the propellant.

The woman cradled the weapon to her chest and stoked the side of the projectile affectionately. "This lovely weapon of destruction is a Panzerfaust 60. It's a disposable weapon designed to wreck the most amount of shit in shortest amount of time and it's about as simple as this weapon type get. It's also light enough for someone to carry a couple without being slowed down. It might not outright kill a titan but it will blow off limbs, shred muscles and tendons, and generally wreck the bastards caught in the line of fire. A volley of these will make it much easier to administer any finishing blows required."

The roar of a Titan dragged their attention to a jogging Titan coming their way. Seeing both them stiffen, Astrid rolled her eyes. "Relax. It's just an illusion. Oh and don't stand behind me or within ten feet to any side."

The woman crouched down on one knee, positioned the projectile in an underarm firing position, opened up the sighting mechanism and selected the range she would need. Her eyes darkened with bloodlust as she fired once the creature was in range.

The end result proved why she was cautious about producing these weapons.

"The Panzerfaust are for infantry or simply the Survey Corps. We will need something heavier for surprised attacks. Many of such weapons which might be effective against them aren't practical for this world. Your cannons are okay, but aren't mobile which we need. My personal preference and suggestion is a multiple rocket launcher. Accuracy is not their strong point, although probably no worse than a smoothbore cannon. But they do have a hefty payload capacity and they're simple, cheap, effective, and reliable. They do take time to reload, however, and their ammunition is bulky." She paused in her explanation as if considering something. "Field tests would be required to see whether they will work in this world. I think using swords as your primary means of bringing down titans is indescribably stupid, but a titan with a leg shredded by a rocket blast is going to have its neck conveniently close to ground level, and at that point finishing them off with a sword lets us concentrate on more important things."

Astrid smirked at the two. "Often mercenary and criminal jobs required staking out the target over a period of time to get the required information without anyone knowing I was there so I developed ways to be stealthy and unassuming. Since titans finding out where humans are is usually followed by them attacking like the mindless beasts they are, stealthy and subtleness is desperately needed here. Humans have some inherent advantages over titans: we're smaller so we can see them from further than they can see us, we operate fairly well at night while they tend to go dormant out of the sun for now, and we have brains. Yes, this will mean getting off our lazy asses once in a while to climb up hills or trees and look around. Once we've located them, how do we get that information back? I'd suggest a heliograph, which is essentially a mirror that we would use to send messages."

The illusion faded to black and everyone was once again back in the basement. Astrid rubbed her head like she had a headache. Erwin dismissed the oddity that just happened and focused on getting more answers.

"You can produce these equipments, correct?"

"These will only work again titans and certain non-human types, but yes. I will require material, time, assistance, and some form of payment for labor costs."

Erwin frowned but nodded at the terms for those items. "Regarding your Kind-"

"We are notoriously difficult to permanently kill," Astrid cut off with a shake of her head. "I have my own plans for how to deal with them, including the Survey Corps providing what assistance they can render. The plans will change once I am certain which one altered events here. Until then, it is better to leave that alone for the moment and focus on the most pressing matters."

Knocking on the latch above them shattered the serious discussion between the three of them.

Astrid smiled like a little kid, a surprising scene after all this."Like food! Eating is important after all."

Erwin suddenly felt like he was out of his depth but he was in too far to do anything but tread the waters around him, hoping he won't go under.

Dinner that night was the single most awkward meal Astrid could ever recall happening to her. This is including the one time some random demon brat walked into her apartment like he owned the place, sat down at the table and took half of her homemade pizza as his own. That jerk had the nerve to complain by saying it needed more spice.

"Can you pass me the salt, Astrid?"

Astrid carefully handed over the salt container in front of her to the blond haired man before her eyes travelled back to Grisha who was cutting the decent sized hunk of pork with more harshness then the task needed.

Carla looked at her husband in concern but struck up a conversation with the Survey Corps member leaving the oblivious Eren to ramble on about nothing to Astrid who nodded and quietly added her two cents when asked.

Thankfully, that torture didn't last long before Erwin decided to be a good person and get the hell out of here. Only after hinting of returning in a few days time for more in-depth details, of course.

The moment he was out of their sight, Astrid stared at the rough grip on her shoulder in annoyance.

"I imagine this is were I am supposed to tell you how I know all this information," mused Astrid.

Grisha grimaced at how bluntly she admitted to knowing things that were best left alone. "That would be helpful."

Astrid sighed as she ran a hand through her hair. "Meh, you only have about four more years left to live so I can't see what you can do to fuck me over long-term."

The man paled at being reminded of the time limit by someone who shouldn't know such things. His only solace was that she didn't reveal his Titan Shifter status. Maybe she did it out of the kindness of her heart.

"Don't go thinking I did this out of kindness or some other foolish feeling. I need your help slightly less then you will need mine, and you can't help when dead."

Nevermind that then, Grisha thought with a crown. At least she is honest.