# Would an ultra-heavy tank be a resource-efficient zombie-extermination unit for an CBRN-contaminated environment?

The question, before you get into the rest of this textual abomination: with all of the context, objectives, and design features mentioned below, is an ultra-heavy tank a resource-efficient means of killing zombies in an CBRN (nuclear/biological/chemical/radiological contamination) environment inhospitable to human life?

Let's say that, in the near future, there's a zombie apocalypse in the vein of World War Z: perpetual-motion, fast-moving, and hyper-aggressive zombies (long story).

Important note: they form chain swarms when they hear loud noises. This is relevant later.

People have retreated, re-established their industrial and technological base, and have mostly systemically exterminated the zombies infesting their country. They came up with the concept of the resource-to-kill ratio; essentially, how do we minimize the resource and/or dollar cost of killing an individual zombie? Their solution to that was to use infantry with bolt-action rifles, as that's about as efficient as you can get without endangering your soldiers: one bullet, one kill.

However, there's a massive area of the country that was sterilized with every nuclear, biological, chemical, and radiological weapon known to mankind in an attempt to destroy the zombie horde in it. Unfortunately, it didn't destroy many of them. There are still millions of the things left.

Normally, the society in question would not want to take back such a godforsaken wasteland, but the sheer number of zombies in it means that it's a threat to anything and anyone nearby, as hordes constantly march out of it to attack the living.

Building a wall around the place and making the zombies pay for it was dismissed as a waste of resources, given the scale of such a project, and the fact that the zombies climb walls like ants.

They can't be met outside the wasteland in a resource-efficient way, either - doing so means mass civilian evacuations in the path of the horde, as well as pulling hundreds of thousands off-duty (say, building new homes, or performing mass burials, or having babies - people who would generally be rebuilding after an apocalypse) in order to meet it, as well as to operate the supply lines keeping the front line fighting.

Since these zombies are both extremely fast and extremely coordinated (for instance, look at this example of World War Z zombies climbing a wall like a horde of ants), sending in armed personnel into the zone in bulky hazmat suits, CBRN-proof vehicles, and mobile decontamination bases means that they're not mobile enough to avoid getting overrun and torn to shreds. A specific vulnerability is that suit or base breaches are guaranteed death even if the zombies don't get you; the nightmarish, radioactive chemical soup the area is saturated with will kill you soon after a suit breach.

Now, fighting the zombies from within an CBRN-sealed armored vehicle helps negate the problem of a suit or base breach: the entire thing is armored, and zombie bites and/or environmental debris will not get through it.

However, fighting the zombies from inside a CBRN-sealed armored vehicle fails due to two major and two minor factors:

MAJOR:

• These zombies pile up on you - potentially by the thousand. Even if you somehow manage to kill a shit-ton of them, your vehicle is going to be buried in their corpses. The odds are that its wheels just aren't going to get enough grip to be able to move. Now, you might negate that by replacing wheels with tracks, but those get clogged with zombie parts relatively easily. Hell, they might even be able to smother your engine.

• It's hard to live inside a tank. Yes, I recognize that people have done it in the past, but if you're on a patrol in the Northeastern American Dead Zone for a month on end inside a sealed metal can with nothing but death around it, you're going to go nuts eventually. Even submariners have more room per person than there is per person inside, say, an Abrams or a Bradley; the only occupation I can think of that involves less room to move around is being an astronaut on the earliest space capsules.

MINOR:

• You're going to run out of fuel eventually. Obstinately, you can go back to base for more, but that's only if you can avoid getting bogged down by the hordes of sprinting, dog-piling zombies - and if you run out of fuel, tough luck.

• Eventually, you will run out of ammunition; there is only so much room for the stuff inside a tank or an armored personnel carrier. Again, you can technically go back for more, but, again, if you run out you're hosed, and it's not like it's easy to fit an airlock onto a tank.

Moreover, going back for fuel and ammunition limits the amount an extermination team can penetrate into this massive dead zone; even if they set up fuel dumps inside it, they are liable to be contaminated and/or overrun.

Enter my solution: the ultra-heavy tank. If you want an example of a vehicle on such a scale, look at the Nazi Landkreuzer P-1000 Ratte, or NASA's crawler-transporters. I'm not saying "build a Ratte" or "build a crawler-transporter"; I'm just providing an example of what vehicles on this scale look like.

Now, there are many glaring flaws with ultra-heavy tanks that preclude their use against human enemies:

• They require truly gargantuan amounts of fuel.

• They're basically a gigantic "kick me" sign for aircraft and artillery.

• Their ground pressure is off the charts, and they destroy any bridges they cross over, meaning that follow-up forces can't use them.

• They're slow.

However, in a near-future war against World War Z-style zombies set in a chemical hellscape, these problems are negated.

• Replacing gasoline-powered engines with small modular reactors, batteries, and electrically-driven motors negates the fuel problem - fuel-wise, the thing can operate for years on end.

• Zombies have neither aircraft nor artillery.

• We'll get to my way around the ground-pressure problem eventually. Moreover, destroying bridges is not a problem, because:

~ the odds are that they're gone already

~ it's not like anyone will be using them anyway; they're in a toxic, irradiated moonscape unsuitable for human life

• Being slow is not a problem, for reasons I will get into.

Moreover, such a vehicle has several advantages as part of a near-future war against World War Z-style zombies set in a chemical hellscape:

• Despite its low speed, its great mass gives it incredible kinetic energy once it starts moving. It can flatten houses, fences, most land vehicles - actually, most obstacles that would impede a lesser vehicle in general, of which there are going to be a lot of post-apocalypse - and woe betide the pile of zombies that tries to climb onto it: the thing just keeps moving. It doesn't have to move quickly, like it would against a human adversary who's attempting to get bombs into it - it just needs to avoid getting piled up on, so that it can constantly bring its weapons to bear on the zombies.

• Unlike a pack of lighter vehicles and semi-mobile, pre-fabricated bases, an ultra-heavy tank is one gigantic thing. There are no vulnerable airlock tubes in-between vehicles, no lengthy decontamination procedures, and no need to climb into a hazmat suit to go to the messroom, or go to the toilet, or to load new munitions into the thing: everything is already inside the vehicle. The Ratte, for instance, was designed with a motorcycle bay, an infirmary, several storage rooms, and its own self-contained lavatory system. Essentially, such massive vehicles have interior supply lines on a tiny scale.

• Unlike lesser vehicles, an ultra-heavy tank is large enough to carry that nuclear reactor I mentioned previously, meaning that fuel is a non-problem for years.

• It's a propaganda symbol: what's better for the spirits of a crushed and depleted people:

~ a bunch of hazmat-suited, faceless goons with rifles, in the same tanks that failed to stop the zombies the first time

~ a majestic, invincible land battleship and its brave, intrepid crew

• Ammunition is less of a problem, because the square-cube law works in the favor of ammunition storage here; since the tank has more inside volume, it can carry a lot more ammunition.

• The crew go insane less quickly; since this thing is, in terms of accommodations, more comparable to a submarine than a tank, longer zombie-extermination trips can be undertaken.

However, there are a number of features that could be incorporated in order to make the thing more efficient:

• No armor. Zombies don't have armor-penetrating weapons, meaning armor is as much of an instance of dead weight as the zombies.

• No artillery weapons. A high-explosive shell is not the most resource-efficient way of killing zombies. Instead, replace the main turret and the entire top of the hull with a superstructure; in it are armored, CBRN-sealed ports with integrated semi-automatic rifles, so that the crew can pop the heads off of zombies one at a time.

• Instead of two tracks, add as many as possible - preferably, mounted next to one another, and using the space in between where the tracks would be on a conventional tank. This ensures redundancy, as well as reducing the vehicle's ground pressure. While this would make it very difficult for the vehicle to turn, turning is not really an issue, since it can be accomplished over long periods of time.

• Add a plow on the front, for getting obstacles out of the way of the tracks.

• Give it cheap, disposable drone scout support for finding and navigating towards large hordes of zombies.

• Add mine flails between the ground and the firing ports, so that zombies attempting to climb it get mulched.

• Add airlocks on the dorsal superstructure, so that cheap, expendable cargo drones can slowly but steadily resupply the vehicle's ammunition reserves.

The standard modus operandi for one of these vehicles would be:

1. Drone locates zombie horde.

2. Vehicle drives to horde to intercept it before it exits the dead zone.

3. Vehicle begins playing loud music, horns, whatever have you, forming a chain swarm

4. Chain swarm follows vehicle as vehicle leads chain swarm away from populated areas

5. As (4) is carried out, sharpshooters inside vehicle terminate zombies.

Eventually, they'll run out of swarms near the dead zone border, and begin pushing further into it. Other than that, no major changes in that plan, other than a return for crew change-out/repairs every 6 months.

Again, the question: with all of the context, objectives, and design features mentioned above, is an ultra-heavy tank a resource-efficient means of killing zombies in an CBRN (nuclear/biological/chemical/radiological contamination) environment inhospitable to human life?

• Comments are not for extended discussion; this conversation has been moved to chat.
– L.Dutch
Aug 17 at 8:53
• "extremely coordinated (for instance, look at this example of World War Z zombies climbing a wall like a horde of ants" -- I don't see any coordination in that video. Just a bunch of mindless creatures swarming on top of each other at the point easiest to climb. Heck, we can see zombies falling off the pile they're forming. If bullets work against them, then dropping bombs at that group outside the wall also must. Fragmentation grenades should be perfect. Aug 17 at 8:57
• All you need is this. Attack from the air! Aug 18 at 13:53

Blimps

• A large blimp costs a few million, similar to a tank, and surely less than your super-tank.
• The zombies won't be shooting it down. They can't swarm it or gum up its wheels.
• Blimps are unaffected by terrain and can travel much farther than a tank. They can loiter around in an area killing zombies without spending much fuel.
• The crew in the blimp are probably safe from ground-based CBRN hazards even if no other precautions are taken. It's unlikely that radiation or chemicals on the ground would harm them hundreds of feet up in the air. For extra protection, the blimp could be plastic-sealed except for the gun ports.
• The blimp crew can be armed with rifles. At 10 cents a shot, this is a resource-efficient way of taking out zombies. It could also be a platform to deploy noisemaking bombs as suggested in another answer. The bombs could be lowered from the blimp into the heart of the zone, left on the ground to make noise and attract zombies for a while, and then explode on a timer.

Or just don't go in

If these are normal zombies that can't reproduce, their numbers are going to do nothing but diminish as time goes on and they wander out of the zone and are killed. A single soldier with a rifle can probably take out dozens of zombies. Just maintain a rapid-response system with cars or trucks so that every time a group of zombies comes out of the zone and attacks, a bunch of soldiers can get there quickly to wipe it out. This would be much more cost-efficient than tanks or blimps, though it would not give peace of mind as quickly.

• Also a note before someone says it: airships aren't made of explodium and almost all problems were human error rather than problems with the airships. In WWII one airship got into AA fire twice, lost over half its gasload and still managed to return and land safely. Modern airships would be even more sturdier with even more redundant systems. I would personally deploy parachute bombs with a speaker below it to maximise the amount of zombies it can kill, after first finding and attracting as many zombies with the airship itself. Aug 16 at 10:03
• +1 for aircraft, but suggest going the next step re the crew and leave them back at base operating the blimp as a drone. Zombies not only don't shoot back, they definitely don't conduct electronic warfare which means that there's no risk of the enemy hacking your remotely operated aircraft. If something does go wrong and the blimp falls out of the sky then all that's lost is the vehicle, the trained crew is safe and no resources are required for rescue. Aug 16 at 11:22
• I love how that sidesteps literally every problem. Although I am now curious how a World War Z zombie swarm might combat a blimp. Some of the behaviors can only be described in Muldoon's voice: "Clever girl." Aug 16 at 15:14
• Honestly, I think this is the winning answer. I'll keep the question up and around in case people have other ones, but I really think this wins. Aug 16 at 18:14
• Your rapid response system could include drones that constantly survey the perimeter, miles inside the cutoff, so your ground troops know where the zombies are coming out hours before they have a chance to attack anything. Aug 18 at 5:21

# No

Your tank is a very expensive coffin.

1. The tank is not a submarine. Enough zombies will literally form a fluid around it, preventing it from moving.

2. All tanks require maintenance. Maintenance free tanks don't exist, they break down. You cannot exit the tank to fix something with zombies swarming around it.

3. Guns, and tanks in general, are great for killing things far away from you. Your tank has a failure state of "zombies are not far away from you".

# Solve it in phases

Each phase's goal is to kill 90% of the zombies in the region.

# Phase 1:

Sort of already complete. You used chemical and nuclear weaponry. This will have reduced the zombie density. You can complete this by identifying remaining high-zombie density areas, and doing saturation bombing with conventional explosives/napalm/etc.

Goal: Kill 90% of the zombies.

# Phase 2

Bombs with speakers. In areas where there are zombies, but not enough to pay for carpet bombing, drop in a parachute a loud speaker and an hardened high explosive device. Zombies are attracted by the loud speaker. Then the explosive device goes off, shredding almost everything in 100 meters.

Goal: Kill 99% of the zombies.

# Phase 3:

Just speakers. Your goal is to find out where the zombies are. Drop solar powered loud speakers with zombie detectors. Vary the sound played (not just the same frequency range) to deal with zombies that are hard of hearing.

Ideally you can use a remote to turn on and off specific speakers, allowing remaining zombies to be moved using audio-based paths to concentrated kill zones.

Then clean up the resulting kill zones.

# Phase 4:

Active hunting. Send blimps over the area with sharp shooters. Build kill-towers in the no-mans land near the edge (or a bit inside) of the contaminated area that attract zombies, kill them, and act as warnings if a swarm is leaving the area.

Use swarm tactics on the zombies. Volunteer patrols in medium-scale CBRN hardened all terrain vehicles search the area, clearing out zombies and provoking zombie attacks. If they can't handle it, they attempt to hunker down as relief is sent, or they flag the attack and just die. Higher intensity solutions (see above) can be used, like a large bomb (possibly they carry a large bomb in their ATV for just such a purpose).

CBRN hardened construction vehicles rebuild roads and flatten remaining human construction (possible hiding places), possibly even rebuilding bridges to make access by humans easier.

Visual-ofactory decoys (for the zombies whose ears are missing) with zombie-detection sensors (solar powered webcams!) are deployed to draw out zombies. These are air dropped into inaccessible areas and deployed by the patrols.

This still leaves a huge problem. If the area originally had 100 million people all of whom became zombies, 99.99% dead means you still have 10000 zombies in the area.

But those zombies will hopefully be unable to swarm and will decay over time.

An example would be a sealed bomb shelter with a few 100 zombies in it. If these zombies are magically immune to decay, that bomb shelter might stay full of functional zombies for many many years before erosion occurs and lets the zombies out a hole. At which point they go and start a new swarm.

# Phase 5:

Passive, permanent defenses. In the long term, it won't just be zombies inside the contaminated zone that are a problem. Zombie outbreaks will happen in "safe" areas. So you'll want to build zombie swarm barriers and safety bunkers to slow swarm spread throughout the safe areas and preserve some of the population when a swarm occurs.

Then you deploy active defences (soldiers with rifles or whatever you find effective) to clean out the swarm and rebuild.

In safe zones, you'll be spending decades or centuries digging up everything to a decent depth and looking for buried zombies to prevent future swarms and make them more safe.

The CBRN contaminated areas will make that harder. You'll end up wanting to build walls around it and patrol them. Even if it doesn't stop every zombie, stopping ones whose arms or legs are missing is a win.

But none of these steps involves building a giant metal super tank.

• "If these zombies are magically immune to decay" - Worth noting that the zombies in World War Z were not magically immune to decay; although certainly more resistant to breaking down over time than ordinary corpses would be, the zombies zombified in the initial outbreak are described as being considerably more rotten by the time of the human counterattack a few years later than their more-freshly-converted brethren. Aug 19 at 0:54

### Rifles aren't the most resource efficient way of killing zombies. Bombs are.

In short, bullets are a really inefficient way of killing large numbers of people. One bullet can only kill one person, at best, but it's much more likely that you'll be spending dozens or hundreds of bullets for each kill instead, simply because of how inaccurate the humans pulling the trigger are.

The best way to kill zombies would be artillery, for the same reasons that artillery is the most efficient way to kill humans: one artillery shell can kill every zombie (or human) within dozens of meters of its impact point. There's a reason why artillery is called "the queen of the battlefield".

If the zombies naturally tend to clump up in swarms in response to loud noises, that just makes artillery even more efficient a method of exterminating them; you just plant a loudspeaker to draw them in, then shell the crap out of the resulting horde to wipe them out by the hundreds or thousands.

• Comments are not for extended discussion; this conversation has been moved to chat.
– L.Dutch
Aug 19 at 2:32

No, your tank will not be an efficient vehicle.

The reason tanks are heavy and even tank shaped is how they are optimized to survive against heavy weapons. Requirements like a low target silhouette or even being heavy due to all the armour fall away once there is no enemy anti-tank weaponry. You probably want something truck-shaped, maximizing internal volume. High sides are harder to climb, and there is plenty of experience and production capacity to produce trucks, even to custom specifications.

The easier solution however will be to drop crews entirely, and stick to drones. Most of the mass you are carrying around will be for protection systems, which you can all dropped with unmanned vehicles. You may possibly need some radiation hardened electronics, but it is much easier to shield a computer than a person.

Given that zombies don't have any electronic warfare capabilities, there is no chance of them jamming any connections. Using remote controlled vehicles keeps the control crews safe, and flying drones can go in and out of the zone, while being completely safe. At altitude they can even keep away from most of the contamination, making them easier to decontaminate and service. Ground based drones can be remotely resupplied with ammo and fuel, only requiring decon for full service, and if they are too heavily contaminated, you can still just abandon them.

As a rule of thumb, if you are going for efficiency, look for the smallest possible tool that can get the job done.

• Both flying and land drones could be used. Aug 16 at 18:13

Different zombie killing tanks, gas, biological weapons, fire and INFINITE POWER

There's plenty of answers already that tell you a big tank isn't cost effective. Lets focus on what would work.

Lets say zombies can use the maximum strength and speed of a human at all times. Their attacks are still swing, kick and bite. Secondary is simply throw enough weight against something with thousands to damage it.

Tanks

First we need not to be overrun. We can make an armoured vehicle with speed and that is high enough you need to climb before reaching the top. Add some spikes aiming down (possibly retractable). Now you have a machine that zombies can throw themselves onto, killing themselves and sliding off again. Simply drive away from the horde that the fastest can catch up, killing themselves. Add a lot of solar panels for recharging and you can go on a long time. Just go into a safe place every so often to recharge. Only long time wear will destroy your vehicle and you can kill lots without firing.

Gas

But why do so much trouble? Chain swarms are a thing! Make a mega mob by provoking a chain swarm. They go to this specific location you have rigged with traps and kill them there. Literal meat grinders, bombs all around or atomic bombs. All can kill a lot. But you can kill so much more with gas. If you get the right one, flesh can practically melt off the bone (fluorine!). You can gas thousands to millions this way.

Biological weapons

Biological weapons are in extent of this. Bacteria or parasites can simply start eating away at the flesh, eventually removing the zombie remains.

Fire

All that meat represents a huge amount if potential energy. Potential energy can be released with a spark. Drop a bit of napalm or just set them alight with a match. With a mega swarm trap this can spread quickly, consuming a large host with barely any effort. You can just ast Bert to go to a big tower or a big open depression. Set off a siren. Have Bert set a torch alight. Bert will just stand there to be devoured. Thank you Bert. Torch will light a zombie or two on fire, which then can merrily spread to hundreds, thousands or millions. Low cost, low technology, low risk (for most).

INFINITE ENERGY

But why not cost effective, but wasteful? Why not if you have infinite energy. Teslacoils all around the edge of your cities, literally vaporising zombies if they get too close.

How you ask? You have perpetual moving, strong and fast zombies. You know what that means!? Big hamster wheels with zombies perpetually going after prey! Or something less ridiculous, but the point stands. You can create clean, stable energy if you capture enough of these zombies and use them in inventive ways to produce power. Power you can store in batteries for tesla coils or highly flammable hydrogen for example! Electrical fire from the electrified fences and the tesla coils will do the rest. Or maybe from the hydrogen flame throwers. The zombies will create a wall of bodies that is on fire. Remove much mass over time thanks to the fire, pose a difficult to extinguish fire that is immediately a difficult obstacle to overcome. The zombies might never reach your building and the bodies will disappear in the incredible heat of fire.

That is how you get the most efficient killing machines. After a bit of investment, you have a potential infinite return. Mathematically there are few things more efficient than an infinite return.

• Zombies for energy - yes, the way to go, lol Aug 16 at 17:51
• Humans are mostly wet, they don't burn that well. Other than that, where can I buy my own Zombiehamsterwheel (r) to power my house?!? I'll take 2! Aug 16 at 20:57
• @Demigan humans are wet, zombies do not hydrate regularly and are dry! The Zombiehamsterwheel(R) is now available at any perpetual motion zombie shop near you! Aug 16 at 21:06
• How Shaun of the Dead.. The physics of zombies has to break down somewhere, though. Aug 17 at 3:16
• Biological weapons with flesh-eating bacteria probably isn't worth the risk of it spreading to other animal life (including humans). This and other answers propose other ways of dealing with the zombies which don't have such an existential risk to the remaining humans. But +1 for perpetual motion energy sources, using the trope against itself. Aug 17 at 13:04

## Agricultural Machines:

What you really need isn't a traditional tank. It's an autonomous agricultural combine. Admittedly, they will need to be specialized, with a broad base to prevent tipping. Large "roadside mower" attachments with spinning blades to chew through zombies on the sides might help too. The large harvesting implement on the front might need some optimizing for humans vs. crops. Ultimately, it's a giant robotic lawn mower on steroids.

Fundamentally, getting rid of zombies is an industrial process. You need a large, robust fully robotic machine that chews through zombies on a regular route through zombie territory. The outside should be fire-resistant, so a stopped vehicle can be appropriately napalmed and recovered. The zombies will be drawn to the machine noise, ground up and spit out in a stream through the back of the harvester (if disposing of zombie bodies is important, a trailer can be dragged behind to collect the remains).

For simplicity, I'd make them electric with a backup quiet, efficient electrical generator. With the choppers running it would be incredibly noisy, but just running otherwise, it could be extremely quiet on a road. If the vehicle was mobbed, it could simply shut down until the zombies lost interest and wandered away. If it was short of fuel, drone refueling craft (form to be selected as desired) could refuel it in field. But the routes would be short enough so it should be able to run on batteries alone. When the vehicle returned to it's base, it could drive into a sealed building and disinfected in a way you wouldn't want to with a live crew.

You would establish routes through zombie territory and start out with your biggest, nastiest machine you can muster. But once the overburden of zombies began to go down, lighter, more efficient ones could run through systematically chewing up and spitting out zombies until no more come out. Then you set a new route and repeat the process. It may not get all the zombies, but it keeps grinding them up until they are quite manageable.

# No

These zombies pile up on you - potentially by the thousand. Even if you somehow manage to kill a shit-ton of them, your vehicle is going to be buried in their corpses.

All your mega-tank does is require a larger number of zombies. However, as you've already provided - zombies have the requisite numbers: https://www.youtube.com/watch?v=uU0DNCV22dU&t=3s

This is worsened by the extremely limited armaments you've listed: "CBRN-sealed ports with integrated semi-automatic rifles, so that the crew can pop the heads off of zombies one at a time." This is essentially useless given the foe you are facing - they'll probably kill more of themselves in the attack than your rifles will.

TL;DR: the solution to fast, aggressive swarming enemies isn't to sit in a metal box, with no exit, and try to pot-shot them at a distance. You've just made a very expensive coffin.

Regular tanks are not the best weapons, but they will do

Tanks are not expeditionary forces on they own. They act within a limited range from a base or a depot. Turning your depot into a huge tank normally would be cost prohibitive.

Think through a few points:

1. Even if zombies can swarm a tank, they can't do anything to it or the crew inside. Just make sure tanks have emergency oxygen supply;

2. The biggest problem of killing zombies is finding them. Swarming zombies are ripe for killing using any kind of weapons. When one tank is being swarmed, make sure there is another one nearby that should make a short work of the first swarm.

3. Set up an "impregnable" base near the infested territory. Use a tank battalion to draw out all nearby zombies and destroy them. After local territory is cleared, move the base and repeat process.

## No, I doubt it is efficient to build an über-tank

I'll take your own arguments against you :

• This über-tank is slow, but it doesn't matter; Niet, the slower your tank is, the more time the infected will have to pile on it. Moreover, you will always get an harder time moving again if you get stuck. Stopping is really risky therefore.
• If you are not pressured into fighting such as when in safe environment, one bullet - one kill is not the most economic way of killing1. Also, a rifle is not accurate on the move due to the vibrations you'll constantly take. But moving is essential, too, so...
• The last pin to the story is that you do need roads and/or stable, flat environment. If you don't, you lose accuracy with rifles, you have an higher chance of getting jammed. An issue which has been brought up just before :).

To reorganize these points : You need to be not moving to shoot accurately, but at the same time you need to be constantly moving to avoid first the horde. You might think that you can go on a stop, hit then run strategy, but your tank is moving slowly; The Ratte was suspected to move at up to 40 km/h (not accounting terrain!), but such heavy tank will get very long accelerations and slowdowns, meaning your effective speed is lower than that. So you're most probably shooting at most half of the time.

Also, beginning a movement is a precarious step on these kind of heavy duty apparels. It's a common problem with trucks that get bogged in mud in the wild, so imagine with something much bigger, which on top is a prototype which will contain flaws.

## More (zombies) over...

And here comes a part frame-challenge answer :

Remember, the Ratte was a project brought up only as a plan, an idea that never got finished. It was moreover designed to be built into a shipyard refurbished for this purpose, not a regular factory, increasing even further its cost in a context of resource scarcity. Because, let's face it, in the new context after a Z-war, you could have at most 1 or 2 running in after 2 years of development at the very minimum. One or two killing not that much every day, and having a chance of getting overrun and lost. Also, since it's a prototype made in a hurry, you will most likely get a failure at some point, especially on any moving parts... Such as tracks! And to repair those tracks you'd need to be outside the tank, which doesn't seem the best place to be :p.

So, is your plan all about having a few key structures that can be brought down after 2-3 years into the war? Ones that could break, be stuck or ineffective?

But most importantly, what do you do with the horde in the meantime? Do you really hope they won't move in any of your towns, including the facilities you brought on to make your tank?

Until the first tank get out of the factory, what do you do? I've seen many people in strategy games focus on what is called the late-game, ie building big weaponries and big troops. This kind of strategy is very inefficient against rush tactics, such as "hyper-aggressive and moving in mobs" enemies are. Here, your generals are having very high hopes that the zombies won't move outside the region as a horde. So high it is surprising that the countries managed to rebuild and have the resources to defend AND build their tank factories while letting one million zombies roaming freely in the lands. This while still having big concerns about those ones to afford to build a mega-tank prototype.

Efficiency comes along with how many risks you take on your investment and how fast you can take your earnings from. Spending several years on a project dreaming that nothing "too" bad happens in the meantime doesn't seem good at all on this point.

## Conclusion

That's a lot of conditions, which makes me think that making simpler things like digging pit traps, walls or moats2 outside the areas, or crafting lures a few kilometers away and burn everything once done (which is even more efficient cost and time-wise than bullets) are much more practical, faster and safer ways than building on a conjecture.

1 : Quick example : Spears are almost free apart from the initial costs and could be used from the safety of the vehicle (just let the zombies come!). That's just one of many, of course.

2 : Yes, they can climb moats and out of pit traps, but if you watch WWZ movie, they do so by using the others as ladders more so than climbing on the micro-asperities of the wall. This means that you still get zombies down there in the end. Ones that you can safely dispose of and reuse the trap after.

• Yes, it's slow, but it can't be stopped. It doesn't matter if they pile up to climb onto it, because by the time they're high enough to get on top the thing has moved on and they're falling over. Yes, one bullet per kill is the best means of killing zombies, because crossbows and bows have greater fallout with range, spears endanger the user, and they're fighting from a sealed vehicle. Presumably, the vehicle would outrun the horde a bit, stop, shoot a few volleys, and move on before it catches up. These tanks are for fighting stuff inside the zone; everything else is cleared and industry Aug 16 at 7:26
• is up and running again. It's less of a war, more of an extermination effort. Also, I doubt these "wouldn't kill that many per day"; sure, there are "off days" where they kill like one or two stragglers, and then there are week-long periods where the guns are firing constantly and they kill like one per second. On top of that, the area is huge - it's not a town, it's an entire region. You can't dig a pit trap across the border of this thing, and these things climb walls even if they have moats. Aug 16 at 7:29
• Well, the zombies in this particular area weren't destroyed effectively with nukes/bioweapons/etc., and people couldn't survive in the CBRN zone to kill them, so chain swarms/hordes of them marching out to attack people was seen as a temporary price to pay until more permanent means of getting rid of them became available. They can be killed once they leave the toxic area, but that means that people need to get out of the way first, as well as mobilize manpower that could be best spent on reconstruction. Aug 16 at 7:44
• I've reclarified my answer, and removed my comments as they're more of a discussion now. Aug 16 at 10:56

No

You are trying to build the most cost efficient solution to killing zombies by building a huge expensive complex and novel solution, effectively land battleships. Even worse, your zombies are fast and stupid, and attack any loud thing.

Have you ever played a tower defense game? Same concept here, except you have multiple noise makers moving them to multiple points.

Run left, run right, run left, repeat ad nausium.

what you need is;

Simple, robust, reparable, built up in a cellular network, using the zombies stupidity and noise aggression against them.

"Sir killer-thing(henceforth KT) #4 is off line, we're switching KT3# on to draw all the zombies away from it."


Then they need to be small enough to be picked up for repair when they break down by anything significantly quieter than a KT or tower. Blimps are an obvious answer, but really it could be electric lightly armored tow trucks, once all the zombies are routed away by loud things... being overwhelmed isn't an issue.

"Opps there is a problem at field1, lead them over to field 2 please."
"Nope it's going to take a while, move them to field 14"


The simple truth is, that your zombies are a threat to humans during the explosive growth, human isolation phase. Once you get safe areas that can't be overwhelmed, and rebuild industrial capacity, their stupidity and aggression bring them down over time. There is a reason in WWz why shovels were the best tool long term.

It's building defenses they can't breakthrough that's the hard bit. because of the ant pile thing. but even that's not un solvable, because the zombies are stupid.

Hell, "silenced" rifles on the wall, and 4 towers with concert sized loudspeakers to run the zombies round and round while you shoot them.

Put fields of whatever around your defensive walls, and arrays of noise makers to move them wherever you want them before the walls get buried under.

Inside your walls, divide things up into cells that zombies get trapped and killed in to prevent explosive growth.

And that's completely aside from that fact that in your world building, you've removed all reasons for us to leave those areas in the first place. Your version of the Armed Forces were stupid enough to render the rest of the planet uninhabitable. Not even smart enough to drop 1 nuke and see if it worked, Hell your "defenders" are stupider than the zombies.

Nuke 1 massive heard of zombies, did it work? Nope
Ok, drop acid on one did it work? Nope.
Okay, lets drop running chainsaws on them out of airplanes, Nope.
Biological an chemical weapons,  But sir they are dead already*, Corporal do it anyway! Nope, didn't work (*mutters in enlisted)
Running Lawnmowers? Nope, but it made a cool sound...
What about Ninjas, nope now we have zombie ninjas..
Cartoon Mascots for sports teams? Nope, but that was funny as hell!

Well heck, lets just NBC the rest of the planet. Not because it works, but because we're too stupid not too. Durr!


There is literally no reason to go looking for the zombies, as even once they are gone, you can't even use the territory outside your safe zones.

First you remove all agency from your zombies. Then from your "defenders". Then you remove any reason to leave the defensive area.

But back to the original question

The KTs themselves can be anything, Modern Robotic lawnmowers with the guards cut off. ww2 tank Mine flails attached to towers, giant wood chippers with ramps all around them. Hydraulically powered pike squares. Metal Schredders.

Hell windmills with machetes bolted to the blades, low enough so that zombies walk into them.

Alternating bands of upside down lawnmowers and loud speaker towers.

1 on, BRRT, 2 on, BRRT, 1 on BRRT.... repeat

Once you damage the legs of a fast zombie enough, it's a slow zombie. It arms, more so, keep going and eventually its head is at ground level.

Infinite stupidiy = infinite time to kill them.

"These zombies pile up on you - potentially by the thousand. Even if you somehow manage to kill a shit-ton of them, your vehicle is going to be buried in their corpses. The odds are that its wheels just aren't going to get enough grip to be able to move. Now, you might negate that by replacing wheels with tracks, but those get clogged with zombie parts relatively easily. Hell, they might even be able to smother your engine."

This is just a gross underestimation of tanks. Tanks can drive through buildings. Zombies or zombie corpses won't even be felt by the people inside the tanks. Further, most of the armor can be stripped off these tanks since the zombies are just meat; they're not shooting back. So your anti-zombie tanks can have an even better thrust to weight ratio, so you will have even less trouble.

But I think you're going about this all wrong if you're actively attacking the zombies. "Chain swarms" mean they can be easily herded around. Lure them to one of these industrial shredders, and then just watch them get chewed up. Industrial shredders easily eat engine blocks, they'll go through zombies like tissue paper. And they're really loud, and thus very attractive zombie bait.

## Why Bother Protecting a Crew?

• Take a standard car or pickup
• Setup a drive-by-wire system (cameras, steering control, etc)
• Strap some chain saws to it
• Put a bomb on board

Remote control your vehicle into the disaster zone, moving slowly, and periodically buzz the chain saws to gather a horde to your vehicle.

Eventually the car will run out of gas, or the horde of Zs will bog it down in spite of the judicious use of the chain saws to thin the crowd.

Now you set off the bomb.

If you use junk vehicles, this whole setup is pretty cheap. You can probably off a few hundred Zs per vehicle, between those you run over, the ones hit by the chain saws, and the ones you eventually get with the bomb itself.

If you think you need meat inside to keep the zombies engaged, I'd recommend livestock.

I don't believe that anyone has claimed that a tank is a resource-effective solution for any problem. They're designed to complete objectives quickly and effectively, but efficiency is not really one of their design criteria (it rarely is in wartime). In your particular case, you have many solutions that are much more efficient.

Forming chain swarms is only a short-term advantage for the zombies. In the long term, it's the key to defeating them.

People that hunt ducks, moose, or many other types of game locate their prey by using a call that mimics that animal's natural call. It attracts the prey into the open where the hunter can fire on it or ensnare it in a trap. You kill your zombies the same way. Record the sound of their call and use a network of speakers (plant them in advance or hang them from drones) to direct groups of zombies wherever you want them to go. Prevent the swarms from growing too large by using a wall of white noise or nature sounds to drown out the sound of their call beyond a certain point. Any sound generated by a human body's vocal system is completely inaudible at a range of 20-30m in the presence of even modest background noise. With a bit of practice, you should easily be able to pull a small group of zombies at will and separate them from the pack by breaking the call chain.

At this point, you're simply herding cattle to slaughter. Pull them off in small groups and lead them into static traps that you've set up ahead of time. Lead them into a narrow gallery where automated blades and hammers destroy anything that moves. Lead them into a fully-enclosed area, shut the door, and destroy them trash-compactor style. Lead them down a steep slope that causes them to tumble down into the large bark chipper below. The point is, you don't need military-grade equipment or even human operators. The entire thing can be an automated slaughterhouse that's operated remotely. Killing via mechanical methods or melee weapons means you don't have consumable ammunition that needs to be constantly replenished. Humans only need to get involved if something breaks. You can fabricate everything from existing farm or industrial equipment. If you're extremely clever, you can generate power for the whole enterprise by burning the bodies of the zombies that it kills.

Replacing gasoline-powered engines with small modular reactors, batteries, and electrically-driven motors negates the fuel problem - fuel-wise, the thing can operate for years on end.

An SMR, from as far as I can tell, is still fairly large. We're talking hundreds of feet in one dimension and a few dozen in the other two. The 'small' doesn't mean "compared to a human" it means "compared to how big reactors normally are".

Batteries don't help you either. To power the behemoth you talk about, it would need a shocking amount of batteries. Batteries, compared to electricity, is not very energy dense. To recharge it would also be a long task too.