Defending Castle from Zombies

Question

TL;DR: You're defending coastal medieval fortress with help of about 1000 people from attack of zombies.

Long version: In my fantasy world, I'm dealing with problem of how would you defend city against zombies. Defenders are very limited in terms of magic and thus, for the purpose of the scenario, it can be treated as medieval defence.

Zombies on the other hand, are low tier magical undead. They are basically corpses, who are reanimated and conserved with magic. Their principle of reanimation uses original muscles of the body, but they feel no pain. To stop them you need to either destroy their head (which is used by magic as core of reanimation) or at least destroy the muscles. In terms of strength, they might be somewhat stronger than normal human, but not by much, and with limited movement coordination, they actually pose threat only due to large numbers.

I'm thinking about what kind of defensive siege weapons could be used to defend against them? For example: Is heated sand hot enough to cause serious damage to muscles, or does it only do surface damage that wouldn't affect such zombies? Are there any wise strategies that you could employ in event of such castle defence?

In this scenario, we're talking about a case where a castle built on a small peninsula, which only needs to be defended from the land-side. About a thousand of defenders is forced to deal with around three thousand zombies a night, for a few days. While zombies aren't fast nor smart, and tall walls of the castle are barrier they can't break, they can actually climb on the walls, with principle similar to geckos.

Additional Details: City wasn't built to defend against zombie invasion. Weapons it has are meant to deal with mortal demihuman invaders, so are the walls. Firearms are not a thing. Niche ideas based on modern knowledge are useful, but provided it's something that can be done quickly improvised.

Thank you in advance.

Answer 1

The best news is that the gates are safe. Mythbusters did a show which included zombies storming a gate. In their demo, they put all the "zombies" in protective tubes. Why? Because their zombies were human volunteers, and it was actually rather easy for the outside individuals rushing the gate to crush those at the gate. If your zombies made a rush for a real reinforced gate, they'd quickly reduce the front lines to goo.

And they're not smart enough to actually bombard the castle with proper siege weapons. This leaves just the case you worry about -- these zombies can climb the walls like a gecko.

Personally, I'd go for weapons that work like windshield wipers along the walls. Heavy tree trunks attached at the top of the castle, sweeping back and forth. This should knock the zombies down without wasting consumables. Falls from that height are going to do damage to the head of the zombies at some point. At the very least, it will do enough damage to permit you to set fire to the zombie bodies in a fuel-efficient manner.

Also, if they only come at night, I'd be digging pits during the day. Pits are a wonderful way to concentrate the zombies to get maximum bang for your buck. You're really looking to make this siege as effieicent as possible. By your numbers, there are 20x more zombies than humans. While we have seen such utter dominations in the past (Cannae comes to mind), it's really hard to take on that many individuals without running out of ammunition. Any breaks in the siege should be sized upon and leveraged to replenish stockpiles.

Answer 2

Nothing

You don't need nothing special. As the late Tywin Lannister put it, "a man above the walls counts as ten men below". That's why throughthout history, castles and fortifications were rarely stormed, but sieged. A hundred men on the castle could easily stop a thousand attackers. 1000 men against 3000 zombies? They won't even tire.

Give them clubs, maces or hammers, anything blunt and solid, and let them smash the heads of the zombies as they get close. If the zombies are climbing like geckos, they need their hands on the wall to climb, so they can't stop the blows.

Answer 3

Grease The Walls

You have big strong walls and unarmed opponents that can climb. Paint the walls with grease, oil, lard. You don't need to win and you don't need to kill them all, just keep them out for a few days (well nights anyway)

Zombies don't use fire so it's not a risk to buildings. Personally 3000 a night against 1000 armed guards isn't even much of a challenge. That's just three zombies per person per night. Some axes for heads, spears for poking and hammers for fingers, the humans should be able to fight that number off with no assistance.

Answer 4

How close to a gecko toes are their hands? Geckos are the masters of climbing so it would be good to see the limits of your zombies.

Specifically whether they can climb across horizontal surfaces. If not, you could have a outwards inclined wall to ward them off

Zombies are in red. The one falling down says "ahhhh!" (splash)

The good guys are in green. They are partying.

The blue part must be long enough so that the falling zombies do not make a heap higher than the walls (see for instance the very beginning of https://www.youtube.com/watch?v=CLWCgMVf6U0). Bonus if you can cover it with Teflon.

Answer 5

Mindless monsters that can only attack from one side, and you've got only very limited magic?

This reminds me of a mindless game from the Shockwave Flash era - which, in terms of internet, is about middle ages. The game is called Defend your Castle. You played it by clicking and dragging:

"But Renan", you say, "this is a fantasy setting, not a computer videogame!" Yeah I know, different escapism mode for geeks. Well, turns out in Dungeons and Dragons there is a level 5 spell called Bigby's Hand - Actually a consolidation of many different spells from the second edition. It works just like that cursor. Don't believe me just because I'm saying it:

You create a Large hand of shimmering, translucent force in an unoccupied space that you can see within range. The hand lasts for the spell’s duration, and it moves at your command, mimicking the movements of your own hand.

(...)

When you cast the spell and as a bonus action on your subsequent turns, you can move the hand up to 60 feet and then cause one of the following effects with it.

(...)

Grasping Hand
The hand attempts to grapple a Huge or smaller creature within 5 feet of it. You use the hand’s Strength score to resolve the grapple. If the target is Medium or smaller, you have advantage on the check. (...)

Just grab a zombie, move it up some four dozen feet in the air and release. Gravity will do the dirty work. Rinse and repeat until you win.

Remember that every extra wizard or sorcerer is another helping hand, so bring your friends!

Answer 6

A good old moat will do its job of keeping attackers away (image source)

Then your defenders can focus on taking rid of those accessing the bridge, and as the battle of Thermopylae has shown, good use of terrain act as force multipliers.

Answer 7

If the walls are sloped instead of straight vertical you could effectively remove zombies by building a log storage next to the top of the wall and rolling logs down the wall whenever a group of zombies get near the top. This method would be easy enough to engineer and sure to crush and remove any zombies in the path of the log as it rolls down the wall. Workers could then go outside the next day and pull the logs back into the castle to be reused as many times as needed.

Answer 8

As long as the defenders have fireproof fortifications, and a few days to prepare, they can get by with zero casualties.

They need to pile dry brush around their walls, preferably soaked in something flammable. Wait for the zombies to walk all the way into the brush, then light it. The fire spreads, and the zombies, being too dumb to avoid it, just stand in the fire and burn up.

Answer 9

The zombies somehow have super-adhesive gecko wall-climbing powers? Magic, I suppose? How fast can they climb?

I would tend to think, since they're not much stronger than typical humans at best, they still would not climb all that fast, and would still need to use their hands, and bare hands, to do so.

You gave the defenders 1000 men? How long is the top of the battlements along which they must defend? It sounds to me like they probably have at least ten times more men than they need.

What Hollywood and TV seem to have mostly failed to communicate to most people is that it's ridiculously easy to defend a battlement. The zombies here would be climbing up from below with at least one hand busy hanging onto the wall. Defenders would stand above them behind a battlement, and could just drop rocks on them, knock them off with pole weapons, and the ones that got farther would be immediately bashed and chopped with with medieval hand weapons (axes, maces, polearms) by multiple people standing above them, before they could get in any sort of position to fight back. Only feeble or incompetent or outnumbered or surprised or otherwise incapacitated defenders would have any problem defending in that situation.

There are many historical cases where only a handful of men were able to defend a castle from assaults for prolonged periods, because it's very difficult to get up and over a castle wall when there's anyone on top to kill you as you try.

If you want another trick for defending the wall, try a large spiked ball dangled from a chain, that you sweep along the width of a section of wall, knocking off climbers.

Answer 10

Depending on the zombies, castles would be very effective against zombies. They're meant to withstand sieges, after all. That's the whole point of them. Thus, if the zombies are mindless and cannot use siege weapons themselves, a group of 1,000 people could easily repel them. Using slings to hit the zombies with stones would probably be an effective way to break the zombies apart, since arrows wouldn't do much damage to them. Just keep chucking rocks at them to gradually dismember them, and you'll be good. Rocks are easy to come by and it would not be hard to make slings for a hundred people. Plus, it would not be difficult to train people to use them with some effectiveness. Other kinds of weapons meant to drive of intelligent attackers would be just as useful. Most of all, I think flaming pots of oil would be especially potent, since the zombies would be consumed by the flames. Of course, you'd have to consider setting the area around them on fire as well, so that could be a big deterrent against that particular weapon.

Answer 11

as other answer already say, do as fortification usually do.

like throwing stone or brick or other hard object from the crenelation or machicolation if the zombie try to climb (hopefully crush their head or bone to make them unable to move) or try to burn them with any flammable object.

also if the castle have water moat i suggest it link with strong current or wave like from river or ocean or put a creature that can eat the zombie in the moat or it contain flamable thing like oil just in case the zombie can pass the water since i assume they dont need oxygen to breath and they still can float to move or swim or just walk through the bottom of water by wearing heavy stuff like metal armor.

my concern is more on your food supply though if your zombie never rot, since i expect they dont really need to eat while your men still need food for energy.

but honestly i dont think someone will need castle to defend against zombie they have advantage in attricion if they dont rot to cancel the magic, by turtling yourself it will only increase dead body into zombie from unfortified village, in my opinion you need is offense and bait (use cavalry since i doubt the zombie can ride or is there a horse zombie too?) to entrap them to flammable area like flammable forest or plain full of dry grass and burn the area or goes to higher place and lit a balls of hay and roll it to the zombie bellow or other type of fire trap or tactic.

Answer 12

Instead of using tree trunks as wipers, all you would need is a tether, such as a chain or rope, and a heavy weight, such as a big rock. Using a pendulum action it could either deal significant damage to the zombies by smashing into them, or just cause them to lose wall contact and fall. Keep the counter weight and tether well greased to inhibit seizure by the zombies. If a zombie did manage to grab the anchor you would have several options; Increase swing to have centrifugal force remove them, hoist them up to the waiting weapons of your rampart defenders, or drop the whole thing to the ground. Rocks and rope are abundant and expendable and will give the zombies no advantage.

Answer 13

Big shredder/grinder on the road the castle.

The thing about mindless attackers is that they don't think where they go, so placing a giant two shaft shredder on the road to your castle (with a drawbridge to allow people walking during the day) will probably be enough to process them from undead attackers to biological waste.

If some actually make it through - your classic castle defence techniques are your friend - throwing rocks, shooting flame arrows or dumping boiling tar on them should do the trick.

Now if you want efficiency - you can make it water powered, like a river mill, or you could make water flow below it to wash the unwanted biological waste away, you could add an angled slippery slide that would make sure the zombies can't escape the shredder etc.

And where to get that in simplies form? While not easy - digging the needed hole quickly should be possible with this many people, the shredder mechanism could be created from stone (mill stones for example) and connected through a shaft to whatever powered the city mill or other human powered mechanism could be used.

Answer 14

Interesting question and I thought I'd give my input! I was at Pembroke Castle (in West Wales) over the long weekend. This seems like a great castle to use as an example as it was never taken by siege, despite having stood for around 925 (from memory) years.

Now part of the reason for this amazing legacy is that they are surrounded from most sides by the sea, but I'll pass over that obvious advantage since we are talking existing city rather than "best place to build", and it sounds like you've already got a pretty good location.

I'm going to talk murder holes, but I see no reason for this not to be extended to just tipping over the sides of the walls to deal with the zombies.

• As you've mentioned - Sand.

  • An advantage of this is that it doesn't matter if these zombies are wearing chain mail (as I assume they are probably ex-soldiers in walking dead form. Even plated armour will struggle to contend, since the sand can get through all the crevices. When this is heated hot enough... it would definitely cause some muscle damage.

• LimeStone

  • When heated, there is eminence strain put on the rock. When it hits below, it will essentially explode. Medieval shrapnel bomb.

• Pee

  • No honestly, don't laugh. Best bit about this is it doesn't need to be sourced from outside the walls. You have a whole city creating the stuff and it's a waste product! Great thing about super-heated pee? It turns into uric acid - it's corrosive! This will definitely do some damage to the muscle, if enough is poured.

Next, pokey holes - not sure what they are actually called. Add some slits into the wall and stab anything that gets too close with a spear to the head. Make sure they are too narrow for the Zombies though.

Answer 15

In ye olde day, hot oil used to be dropped to those trying to burst the gate.

That will do a lot of tissue damage aswell as musculature, especially if you send a flaming arrow down after it.

Answer 16

The challenge is really the other way around.

How can any number of dumb zombies ever hope to get into a castle without smart human guidance?

Siege warfare is difficult; it takes mining, siege engines and elaborate earthworks to have any chance of success.

I challenge you to find a way that the zombies could win, given how easy they are top lure into situations where they can easily be destroyed one by one. The defenders can just build a narrow ramp witha trap door at the end leading to a meat grinder (with suitable bait just out of reach) and mash the zombies one at a time.

Answer 17

I'll throw a penny in..

give everyone a nice light weight cane/ 'don't actually know what this is called' but it's the same principle, a cane but on the end it has a C shape, for hooking things. Use one of those and simply lift the zombies chin so it's centre of gravity is pushed away from the wall and they fall off.

although this has already been stated, just by pushing the zombies off.. the difference is the mechanism, people suggested maces/hammers/axes all of which will tire you out, if you have to survive all night, even with soldiers on shifts they will get tired and that is when you're going to get vulnerable

Answer 18

I forget what it's called but some castle walls had the top area wider than the wall itself. This meant that any ladder had to be free-standing, it couldn't rest on the walls. There were also murder holes in the part that extended to permit attacking those trying to climb up from a position of very good cover.

Just because a zombie can climb a castle wall (remember, they're going to be rough, not slick. I recall a bit of news out of China of a castle where some people would climb the wall simply to avoid paying admission) doesn't mean they can climb an overhang.

Answer 19

You stated this is a fantasy setting, so what if you fight fire with fire? There's no way these zombies just exist, most likely a necromancer is sending them to distract those inside the castle from the realthreat. However, if a necromancer can raise zombies to life, logic follows they can command zombies, or else why would you do it? In other words, why not have your resident necromancer take care of defending the castle with his zombies? They won't tire, they'll be directed through telepathy (I assume) so no problems with "mindless zombies", and they're completely expendable. Of course, if you have a necromancer, he could just take control of the incoming zombies....something's not right here, the enemy necromancer must have something truly diabolical planned to negate this huge disadvantage. Perhaps the resident necromancer is secretly on his side?

Answer 20

Location, Location, Location! Set up your castle on the rocky coastline at the steepest point. If the sides are not steeply sloped, do some construction work and get those sides in top-top near vertical shape. Like this:

Now all of the horde must cross a very narrow chasm or work they're way around the heights. All you have to do is push them off. Maybe you force them to walk around the castle's side and have a section of wall that moves in and out forcing them to fall (ala RPG style) or maybe you simply roll big objects down the bridge across the chasm. Maybe you run out of stuff and simply have the troops set a phalanx with their full length scutum shields and start pushing zombies over the edge.

A person can very easily break a leg on a bad fall from 10 feet. You're tossing zombies over the edge of 100 feet or more, possibly also tumbling down the slope after the initial hitting of the deck.

Bones will break, limbs snapped in two or bent backwards; heads spilled out on the rock. Should your zombie survive the fall, they'll be a mangled mess. It really doesn't matter that they don't feel pain - limbs don't function broken. So, there they lay at the bottom of the cliff until the magic runs out or the next zombie to fall crushes their skull on its way down.