# How would a war between immortals be fought?

Imagine a world similar to medieval Earth (technologically), populated by humanoid beings. For all intents and purposes, they are humans - they talk like humans, think like humans, have human-like culture - with one exception: they are all immortal.

Wars will still happen because these immortal people still have the same emotions as we mere mortals: Greed, love, lust, desire, and a host of others. They want more land, riches, jewels, power - all the things that many normal humans want. Given that they have the same inabilities to work out their differences peacefully, they go to war.

The thing is, they can't die. If they lost some body part - say, a head or a buttock - that part is regenerated in a matter of seconds (say, two or three). Energy expenditure is minimal - negligible, even. Major injuries are but inconveniences to this race. There's simply no point in trying to kill people.

How will these medieval immortals fight a war? I have two main ways in mind:

1. Focusing on harming the enemy as a way of trying to slow them down.
2. Focusing on destroying resources.

Which path would the immortals take (and how would they go about doing it)?

• Can these beings starve to death? Or alternatively, what happens if they are deprived of food and water for a long period of time? (Immortality is such a tricky concept...) – a CVn Sep 15 '15 at 15:03
• What happens with embedded wounds? Would the healing take place around it? Consider, for example, several bullets or spearheads embedded into an abdomen: if the wound heals around it, potentially you'll end up being a solid core of "foreign objects" surrounded by a human body. Taken to it's extreme, this could be repeated ad-nauseum to create a super-size body as the "human" components stretch out around the embedded objects? – kwah Sep 16 '15 at 23:44
• A normal human would heal with embedded things (eg bullets) would remain in-situ and scar tissue etc would grow around it or would otherwise become a damaged-beyond-repair body section. That is somewhat confusing/inconsistent with cleanly amputated body parts regrowing in their entirety without damage as presumably internal body parts should also regrow in their entirety with no damage in the same manner? For instance a section of intestine that has been damaged should presumably reroute around any interruptions to restore previous (unused?) function or a severed kidney would regrow? – kwah Sep 17 '15 at 1:03
• I am going to put the enemy in a mixer and make an enemy 'juice'. Then am going to drink that...What result do you expect for this 'solution'? – MoonMind Sep 17 '15 at 10:25
• Immortal often means something that could live forever naturally but not necessarily something that is invulnerable to pain, damage or death. Most immortals from our history could be killed somehow. – TafT Sep 18 '15 at 7:35

# Focus on imprisoning

If you are naked in a cage, you can be immortal as much as you want, you won't be able harm me (in most situations, anyway).

• Also what comes to mind: shackles, weights, and a deep section of ocean. Or, even better, trap them under running lava - essentially "freezing them in carbonite", as well as being incredibly painful, if your immortals are lucky enough to have an active volcano. More simply, dig a deep hole, shove them in and fill it... there's all kinds of ways to trap people in a way that basically ends up as death. – DoubleDouble Sep 14 '15 at 21:56
• This is the ultimate fear of an immortal - to be trapped.. forever. Typically this would be phrased as "trapped inside a volcano" which is one scenario that would effectively eliminate Wolverine – slebetman Sep 15 '15 at 6:24
• @DoubleDouble this seems to be a combination of nuclear waste repositories and mine fields. I expect this to be a huge annoyance for their heir. Imagine every time you dig a hole in oder to build a house or similar you potentially excavate a "fallen" medieval soldier. – Angelo.Hannes Sep 15 '15 at 8:23
• @talrnu I think you may be overthinking it, you can of course reason that once an eternity some prisoner will escape, but for the vast majority these prisoners will be trapped forever. As long as you can keep more enemies trapped than the opposition this is a viable way to fight wars. – DasBeasto Sep 16 '15 at 19:22
• This answer and comments are making me really glad I'm not immortal – Aurast Sep 17 '15 at 20:10

Others have asked and answered these questions more than 2000 years ago. Just read literature about any pantheon of gods and you'll find a lot of great patterns.

• Gods can be banished (from places or social gatherings, not from a plane of existence)
• Gods can be imprisoned
• Gods can be tortured (chain them to a rock and send a bird every so often to eat some of their liver)
• Gods can be tricked
• Gods can lose social standing
• Gods can lose ownership

With imprisonment and torture, they have options that are similar to killing. In warfare, they would likely either use weapons that inflict pain, like fire, or weapons to restrain an enemy like nets. Cutting weapons like axes, swords, and halberds will be useful too because even if their sword arm regrows after 3 seconds, the new arm won't be holding a weapon anymore. Depending on the exact rules of their healing, poisons and weapons like barbed arrows could also be very helpful. And of course, they'll use everything that can permanently immobilize a temporarily disabled enemy like shackles, or untrained soldiers in the back that are just there to hack away at the fallen enemies.

The goal of a battle will be much the same as it was in medieval times: To rout the enemy. Once one side believes that they will lose, some soldiers will run away to avoid capture, which will increase the pressure on the remaining soldiers to run away too.

Inferior armies would hide behind fortifications, just like human armies of the time did, and the advancing army would develop all kinds of siege weapons to weaken or remove advantages offered by the fortifications.

Wars are always incredibly expensive, and are paid for by the winning side (ideally) with the spoils of war. If there is no chance for spoils of war there will be no war, for financial reasons. Destroying resources will deny them to both sides, so that is a tactic which is much more likely to be used by the losing side, same as with mortals.

Addendum: I feel the need to address the many answers that say there wouldn't be wars. Imagine that we start without wars. Then 10 immortals team up and figure out that they can just go to a house, easily use their superior numbers to shackle the family living there, throw the father into a well, and have fun with the wife and the daughters. Then these immortals continue to go from house to house and repeat the process until the people realize they can group up too, into groups larger than 10.

Then they capture the 10 troublemakers and punish them by making them into metal statues for eternity. At that point, the immortals have figured out that larger/stronger groups can dominate smaller/weaker groups, which is the basis of warfare. Next, they'll come up with the weapons and tactics needed to defend themselves from other groups (if they're nice people), or to dominate other groups (if they're not so nice people).

Since they are immortal and can presumably reproduce, overcrowding and armed conflict are almost guaranteed to happen at some point.

• Most pantheons of gods are much older than 2000 years. – Angew is no longer proud of SO Sep 15 '15 at 7:49
• @Angew but not older than 5000, so not bad estimate. – arivero Sep 15 '15 at 13:18
• Good answer; I would add that literature also suggests that the gods engage in proxy warfare. Athena doesn't go to war with other gods directly; rather, she subtly influences the leaders of the Greeks to damage those among the Trojans that her enemies hold dear. – Eric Lippert Sep 15 '15 at 14:21
• @Eric Good point. I wasn't entirely clear if these immortals live alongside humans, or if they are the only human-like species on their world. I assumed the latter. – Peter Sep 15 '15 at 18:57
• There's also precedence for hurting/killing mortal things or persons the enemy god cares about. – Raphael Sep 16 '15 at 15:57

Death is something that is almost universally feared. Remove it, and things changes surprisingly.

# 1. What people do

Most people would not try to do things which have very low chances on succeding and possibly cost their lives, like trying to sneak inside the enemy barracks to steal something or so on. These things are normally suicidal missions and failure would likely result in death. Now things are different, suicidal missions could be viable in some cases (if you don't get caught).

Violent sports now could became fun. Ever dreamed about jumping off an airplane (or a very high cliff) and splatting in the ground just for the fun? No problem with that. Do you like the idea of jousting without using any armor? Then, enjoy the fun.

Economy becames very different. There is much less need in eating, drinking water, hunting, farming, etc.

# 2. What people do to harm other people

But, in order to punish someone, now you don't have limits to torture. What about throwing someone to swim in a lava lake? What about being forced to eat/drink red-hot liquid iron being pumped directly down your throat? What about being continually crushed and sliced by hundred of sawblades for some hours? Or days? Or years?

People would be then punished by imprisioning and torturing. There is no limits for cruelty anymore. Wars would be fought with this in mind.

Since you can't kill your enemies, you would likely focus the war into imprisioning and torturing them, and destroying things that they value. By the way, tieing your enemy to a rock and throwing it out in the deep sea or just buring them alive very deep (possibly within very solid rocks like concrete or basalt) has the same economic/political result as killing them. Nobody will ever see them again and they would not be able to do anything that is noticeable to his fellow fully-living humans.

So, instead on focusing on killing and the threat of killing, the focus would be on burying people alive forever or threating in burying them alive forever, which has almost the same practical results.

Fighting would be very different. Attacking someone with a sword or with an axe is useless. What is useful is trying to immobilize as many enemies as possible, and then take them away as quickly as possible for being imprisioned forever (before someone rescue them or they free up theirselves). This could be achieved with traps (like camoufled holes in the ground) or with handcuffs and ropes (preferentially metallic ropes that can't be cut out with a knife). Kidnapping becomes very important in warfare. Developing drugs that leads to paralyzing or weakness also becomes effective.

Battles would be fought as armies trying to capture and remove from the battlefield as much as possible of the opponents. So being trained in martial arts that enables immobilizing the oponent as quickly as possible, like Judo or Jiu Jitsu (but on strange but interesting variations to be fought by massive teams), becomes important. Technics and tactics that focuses on trying to rescue captured friends or being able to escape after being captured are also important.

This type of battle could result in an interesting type of olympic collective sport - Massive immobilization martial arts.

# 3. Physics

By the way, when people regenerate a lost body part, if the strange physics laws on this world don't immediatelly destroy the lost part when the larger part of the body regenerates, we have a violation of the mass conservation law which implies in the violation of the first and second laws of thermodynamics. This could be interesting: By continuously dismembering someone we could create an engine capable of Perpetual motion, since it would be able to continuosly regenerate out of nothing the fuel that it consumes.

Also, since we have violation on mass conservation law, after some millenia of raging bloody wars, Earth's mass would increase and gravity would also increase too. After some billions years, Earth would be transformed into a fiery planet where everyone is constantly being melted and/or vaporized and regenerating. When the Sun enters the supergiant branch and destroys Earth, people would then be constantly vaporized and regenerate in the Sun, and that is indeed very painfully. But this would still become worse when the Sun turns out to be a white dwarf, and that will be still more painfully. To finally make things worse, in some trillions or quadrillions of years in future, this would produce enough mass to the point where we end with a black hole full of people experimenting a new definition of pain and suffering and realizing that they really don't need to die to achieve what could only be described as having their souls being tormented for eternity in what could only be defined as hell. So, surely they will be cast out into the outer darkness; in that place there will be weeping and gnashing of teeth. And the black hole would still be gaining mass, which means that if the gravity gain (i.e. gravity derived over time) is greater than some formula that sums up the universe inflation and hawking radiation, this would result in a Big Crunch in some veeeeeery distant future.

If the regeration happens in a way where there is no mass gain, by destroying the dismembered body part when it regenerates back into the greater body part, we essentially have some form of moving mass and performing work without releasing energy. This could then be engineered into a perpetual motion machine, although this would still be somewhat complicated to achieve, but surely doable. Since we have that energy can be converted to mass as in $$e = mc^2$$, we still are able to create some machine that is able to produce mass out of the nothing. Eventually, after the Sun engulfs Earth and evolves to be a white dwarf, this constant energy gain would be able to turn itself on mass gain under the strong white dwarf's gravity, and eventually (likely in quadrillions of years) be able to produce a black hole and perhaps, the Big Crunch.

In fact, death is something that results on the application of the thermodynamics laws and entropy to living beings. Remove death, and you fatally violated the thermodynamics laws.

By the way, does regenerating works on the speed of light? Or is it faster than light? Or is it slower than light? Or is it instantly? In each one of the four ways, interesting (and possibly paradoxical) phenomena will result when you add relativity into the account...

• Suicidal missions are not viable. Instead of being executed, you get caught and tortured. – March Ho Sep 15 '15 at 10:03
• This post also opens the way for new stories, about people who were buried thousands of years ago, and have been digging their way out with their bare hands all this time... – Mr Lister Sep 16 '15 at 10:42
• I loved your answer so much I just had to create an account here. Thank you for your time and thoughts. – tao Sep 16 '15 at 20:12
• How many people would be required to power a small city if each of their four limbs (and head, I suppose) could be chopped off and burned at a rate of once every 5 seconds? – Adam Davis Sep 17 '15 at 19:54
• @adamdavis sounds like a good follow on question... :) – Tim B Sep 19 '15 at 20:42

## Overview

No war would be fought. First, you don't have immortals. Immortals are beings which do not age or die of old age, but are otherwise susceptible to harm and death. You have invincibles, which cannot be killed under any circumstances. Despite your claim, these beings should not have greed, lust, anger, etc. Mortals hoard resources because they are necessary to survive and thrive. This leads to greed and competition. They lust because reproduction is the only form of immortality available to them. But immortal and invincible beings should have no biological imperative to reproduce, unless there is some other benefit to increasing numbers.

## History

So, it matters how these beings came to be invincible, because that would determine what kinds of drives and motivations they inherited. But logically, such beings should not care about food, clothing, housing, or any other needs related to survival. They should only care about pleasure, whether by art or learning or hedonistic experience. They may develop technology, but if they start at medieval level tech, then their most advanced weapon is their invincibility itself. Even trapping an invincible may be difficult to impossible. If you chain one to a brick and throw it in the deep ocean, it could just break off its leg and regrow it. If you try to bury it under a pile of rocks, it could explode itself or even immolate itself to escape, literally in a cloud of smoke. And technology may well boil down to various ways to attack not one's enemies, but oneself in order to avoid an unseemly fate. This would be a rather peculiar state of affairs, to say the least.

## Tactics

Thus, any kind of conflict would center on imprisonment, as others have noted, but especially on escape, which may defeat capture/imprisonment entirely. Such beings may simply choose to embed a bomb inside their own bodies so that they can detonate at any time, making it nearly impossible to truly trap them.

## Conclusion

Since scarce resources are meaningless for survival, at most, such beings would compete over art and pleasure. Learning would benefit most from cooperation, and is generally not zero-sum. Even competing over resources to, say, build musical instruments or theaters would seem petty and small-minded for such powerful beings. In fact, it is hard to believe that such beings would want to do anything other than advance their technology to match their innate abilities, and this would be accomplished quickest by cooperating.

Strong leaders would not exist because they can guarantee survival or riches, but simply because they would give people something to do. Boredom would be the biggest danger in a world of such beings. This is why intellectual advancement is the most logical pursuit. How they came to be so powerful with so little technology to begin with might be the defining question of their time, given that nothing else in their world is as durable as they are.

• I don't agree with your explanation of terms. "Immortal" = "cannot die" (either of age or by killing). "Invincible" = "cannot be beaten". "Unaging" is a better term for how you understand "immortal" and "immortal" is how you understand "invincible". Invincible being cannot be imprisoned, or in a strong sense, even cheated or beaten in games of chance (but can commit suicide, if not immortal as well). If you have some proof that English usage of these words distracted so much from original Latin meaning, add it to your answer, otherwise it's a reason not to upvote this otherwise good answer. – Pavel V. Sep 15 '15 at 11:54
• Using a bomb won't help them escape, unless they keep nuclear weapons in their bodies, they can't reliably destroy the prison and escape. – March Ho Sep 15 '15 at 13:23
• I find the argument interesting that an Immortal could escape the deep ocean. "It is frigid: in most places, temperatures are between -1 and 4⁰C. Worse, the pressure is a crushing eight tonnes per square inch, about a thousand times the standard atmospheric pressure at sea level. It's like being crushed to death in a freezer." Good luck cutting yourself free when you're a condensed piece of frozen immortal mush. – DoubleDouble Sep 15 '15 at 19:24
• Lawnmower Man - @PavelV. is, I think, correct. – HDE 226868 Sep 15 '15 at 23:17
• @PavelV. I agree with Lawnmower Man's use of immortal to mean unaging and invulnerable to mean cannot be harmed/killed. I'd suggest that this passage "The absence of aging would provide humans with biological immortality, but not invulnerability to death by physical trauma; although, mind uploading could solve that issue." from en.wikipedia.org/wiki/Immortality supports that idea that immortal is live for ever without agin but invulnerable is cannot come to death in any way. – TafT Sep 18 '15 at 8:03

If a full war were to be waged, I would imagine it would go on for quite some time, until one side is eventually capable of imprisoning most of the other side, as @Lohoris suggests.

However, after the results from that war, I imagine immortals might be loathe to try and resolve difficulties in such a time-consuming and painful method in the future.

There could be a number of different ways immortals might decide to resolve conflicts instead:

• Duels
• Vote by Popularity
• Luck-based contests or gambling
• simulated war via mortal proxies (If any suitable animals may exist)
• Proxy is the most likely. Indeed, I haven't seen a war yet that was averted by a duel or lottery. – PyRulez Sep 14 '15 at 22:35
• @PyRulez en.wikipedia.org/wiki/Horatii, and more historically en.wikipedia.org/wiki/Battle_of_the_300_Champions and en.wikipedia.org/wiki/Battle_of_Champions (among other examples) – SJuan76 Sep 14 '15 at 22:59
• @PyRulez I'm not so sure. "War by Proxy" seems a lot like gambling to me, especially depending on what animals are available - it might be more similar to a scaled-up dog fight. – DoubleDouble Sep 15 '15 at 15:59
• @SargeBorsch for the same reason countries have armies of soldiers instead of gamers. If you beat me at Quake, I punch you in the face, and it doesn't matter who won the match. Whichever proxy can be bypassed by a superior violent force. – Davidmh Sep 16 '15 at 23:26
• Not exactly (although in all honesty, peasants were considered much more expendible so that might fit our definition of proxy). But I would consider the immortal scenario similar to what we have now. Modern troops are certainly not invincible, but a troop-vs-troop assault is not going to be as effective now as it was even 50 years ago, much less 500, so the parallels are strong. – corsiKa Sep 17 '15 at 16:46

You say that these people is like humans. No immortal would be like a human, since our mortality is a cornerstone of everything that makes us human.

There is no reason for these people to feel pain. Pain is there to stop us before we do something fatal. No fatality, no pain.

There is very little for these people to fear. Fear is there to stop us before we do something that would be painful. No pain, no fear.

There would be no need for these people to be social at all. Human originally banded together for mutual protection. These people have no need for protection.

Military discipline would be impossible. It is built partially on the mutual protection idea and partially on soldiers fearing their officers more than they fear the enemy. No need for protection, no fear in general, no military.

These people aren't anything even remotely close to human, and it is impossible for us to guess how they would behave.

• You're making a lot of assumptions here. Death is certainly not the only thing to fear. There's still concrete and abstract things aside from your life you are capable of losing. – Cubic Sep 15 '15 at 15:24
• @Cubic and spiders. Spiders are also something to fear. – YoungJohn Sep 15 '15 at 21:32
• Some interesting points, but I disagree. Why wouldn't they feel pain? Pain applies in all situations where someone could undergo harm, and even though harm would not kill these beings, it could slow them down. – HDE 226868 Sep 15 '15 at 23:19
• The number one reason they feel pain is because the author said. So that's what we are working with here. – NachoDawg Sep 17 '15 at 8:40
• Pain evolved to tell us that we were coming to harm and should escape or avoid the situation. If these beings evolved from humans (or human like beings) they might have left over evolutionary baggage that is of no direct use to them. Pain, hunger, lust, cold, heat, thirst & more would be like an appendix. Still there and still unpleasant if it goes wrong but of no need. This could also explain their drives for resources to slate their immortal hungers that server no logical need. – TafT Sep 18 '15 at 8:07

They don't need resources to live so destroying resources has no effect.

They cannot be slowed down at all for more than a few seconds so hacking limbs off is ineffectual. Even if one were completely dismembered they would simply regenerate as soon as they are left alone for 10 seconds.

Torture is no good since they cannot die and cannot elect to commit suicide.

Imprisonment is ineffectual since it takes additional resources to mind the prisoners and given they are immortal, statistically speaking they will eventually escape, unless::

Second Edit: Actually you can disable an immortal permanently by casting him or her into the heart of a star or gas giant, and somewhat less certainly by dropping them onto any other planet from which gravity well they cannot escape. If the immortals develop technology which could overcome these gravity wells, then your only remaining recourse is a black hole.

I do quite like the idea of:

# "immortals riding space-dragons wrestling on the event horizon of a black hole at the centre of the galaxy at the end of time (TM)"

• "Imprisonment is ineffectual since it takes additional resources to mind the prisoners and given they are immortal, statistically speaking they will eventually escape." - I disagree, throw someone tied to a rock in the deep sea or just bury them alive very deep. How is this not effective? How they will eventually escape in say, less than a thousand years if ever? – Victor Stafusa Sep 14 '15 at 23:31
• they are immortal forever. eventually the iron bars will rust and decay and they will be free (possibly mad, but free). – rumguff Sep 14 '15 at 23:37
• @rumguff Except, when the iron rusts, they will not be free. They will be compacted into the earth so tight that they cannot move. I don't know if you've ever had to lift dirt or rock before, but its very heavy. A cubic foot of dry (loose!) dirt is 76 lbs Just 10 feet deep, lets say you are over 5 feet tall, (highly likely), you have more than 76*10*5= 3800 lbs of dirt on top of you, and that's a very generous estimate. The heaviest record dead lifts are at just over 1100 lbs, and it would be much harder than a dead lift. – DoubleDouble Sep 15 '15 at 20:01
• why would they be compacted in the earth? – rumguff Sep 15 '15 at 20:06
• Hmm... "immortals riding space-dragons"? I don't suppose you've been reading Raymond Feist? – Mason Wheeler Sep 15 '15 at 21:11
1. Capture them;
2. Chop them down as fast as you can (5 persons chopping a limb at the same time should be enough... trial and error);
3. Immediately stick their stinking regenerating body parts in small and strong metal cases;
4. Drive them as far away as possible in different directions and bury them deep in solid rocky ground;
5. Cover each of the burial places with large enough stones.

That should make their immortal arses quiet for a long time.

They would cut themselves in half so that each half grows back to the original. Exponential growth will then allow them to overwhelm the enemy. At least this is how the immortal microbes go about their business.

• Interesting idea, but as I stated, only one immortal will regenerate after a large injury. – HDE 226868 Sep 20 '15 at 13:30

Immortal, not invincible...

My line of thought/questioning differs from existing answers which focus purely on physical imprisonment and psychological warfare. Instead, depending upon the mechanism of healing it may be possible to disfigure (and disable) your enemy instead.

I also suggest that it may be possible to disfigure yourself to your own advantage.

Disfigurement via damage/healing cycles

For example, given a partially broken bone or other similar internal injury, the healing process may be influenced to heal in abnormal positions - for example at a slight angle. Repeat ad-nauseum and it may be possible to encourage a poorly-healed limb to rotate upon itself and/or in wierd and wonderful directions and shapes.

Embedded "stuff"

Given that healing process may be perfect at repairing/adapting bodily function, it may be possible to embed "stuff" within a body (for example a bullet), then have the body heal around it.

Presumably the healed body would have the same mass, with the addition of whatever is embedded. Repeat a few times until the immortal being exists as a skin around a solid "core" of embedded 'stuff'.

Do this with all body parts and slightly larger items than a bullet and it would be possible to configure a body to be much larger in size than a normal human.

Combining the above for the offensive - GIANTS!!

By using repeated breaks/repairs to extend limbs (instead of deform them) and the packing of "stuff" withi+n a body, it seems feasible that by taking advantage of the healing processes then giant beings can be created.

Drawbacks

• Given the ability for severed limbs to heal back perfectly (with the severed part(s) disappearing), all it would take is for a deformed being to be restored is to systematically remove various body parts for them to be replaced "as new", undoing the earlier disfigurement/disablement work.

• Presumably pain would only be felt for a second or two while injuries/wounds heal, but this may still be a significant inhibitor of self-inflicted disfigurement.

• It is an assumption that the partially healed areas and stretched areas of flesh would increase in strength/capability. I suggest that this seems reasonable in the case of muscle where strength is increased in normal humans via repeated small tears and repairs.

Focus on Psychological Warfare

If you can't kill an immortal, it's effectively the same as if they have really amazing armor. The Art of War dictates that you shouldn't make frontal attacks unless you have overwhelming force. There is no such thing as overwhelming force to a person who regenerates a body part in seconds. You have to make them not want to fight you anymore. Demoralize them so completely that they simply cannot fight anymore.

Hence to fight and conquer in all your battles is not supreme excellence; supreme excellence consists in breaking the enemy's resistance without fighting.

Outsmart them

It is instantly obvious that open, frontal attacks in these circumstances are pointless so don't do it. Attack them sideways with methods they don't expect.

• Be where they do not expect. Move your armies in such a way that they do not or can not anticipate where you are or will be.
• Anticipate their plans and preempt them. Having spies and moles in their organization will make this much easier.
• Build an economy that out-competes theirs. Pursue any and all economic advantages. Business is cut-throat already. Economic warfare among immortals would be especially bloody.

## This Is Why We Can't Have Nice Things

If immortals themselves can't be usefully harmed directly, and if you're tired of the "what if we put them through a wood chipper over and over again..." shtick, let's consider the next big issue: if these immortals are like humans, they care for things other than themselves.

Pets, plants, houses, gardens, gifts they were given (or are working on to give to someone else), monuments, relics, symbols, etc. These things are all anything but immortal, and just as humans can care for things they know won't last their whole life (pets with short life spans, flowers, even other mortal humans), these people should care about something.

Sadly, in a state of war, these things become the primary objectives. If you can't destroy your enemy, destroy what your enemy cares about.

## Pillaging, Razing, Raping, and Looting

Your immortals should tend to want to defend the things they care about, rather than merely themselves. Some immortals will just want to watch the world burn, having given up on caring for anything impermanent and inferior, while others will likely come to hold the idea that just because something won't last forever is no reason to let it be taken away prematurely.

Greed, jealous, and envy should also still exist. Why do those people get gold-plated crowns and comfy chairs - what, do they think they are better than us?

## Everything has a season and a time

We can enjoy it while it lasts, grieve, and then move on to the next experience, and your immortals should understand that - again, all the more reason to develop, build, and protect what you care about. Some will want to hurt others by taking away these things, and some will fight to protect what they have.

## Get them before they get us

Just as humans have problems with pre-emptive attacks, your immortals should too. Sure, the Others SAY their forge is for creating building materials for their city, but that "column" sure looks like a potential battering ram to me! And are those hammers for building, or war hammers?

Your societies may tend to think the other guy is working on siege weapons (weapons of mass destruction), and if they have the facilities they need to build weapons of war then you'd better have some of your own too. Fear leads to arms races, and arms races lead into escalating conflict - and war.

## Siege Weapons Are The New Primary Weapon

Given all the above, why should immortals care about pointy sticks? Sure you can slow down the others, and that will have some value (hacking off legs, pinning them in place temporarily with a big spear, etc), but that's just a means to the new end - destroying stuff.

If the goal of the combat moves from "killing and maiming" to "breaking and burning", the weapons they choose and how they conduct warfare should change more dramatically. Historically siege weapons were not so extensively used for this reason, but with the focus now being on 'things' instead of people siege warfare should see a new golden age!

I imagine hammers, ballistae, flaming weapons (arrows, pots, etc), catapults/trebuchet, hammers, and "area denial" weapons (raining arrows/rocks/shards/fire/caltrops/spikes) will be thrust to the center of the action. You'll still need cutting weapons, but you also need a new strategy: how are you going to make off with the goods in a hurry?

I imagine speed, mobility, and carrying capacity will be a big concern. What good is raiding the enemy city if you can't carry off their giant golden phallic objects? You need wagons, maybe horses (uh oh, those aren't immortal...), and probably other developments that were not the norm in the middle ages.

## Cue Gunfire and Explosions

Remember, too, that cannons and gunpowder are achievable in the middle ages - and in Europe this was not so important partly because of how war was fought. But if hurling a big iron ball hundreds of yards, or making things explode in flames, suddenly becomes more important than accurately hitting individual people, why wouldn't they emphasize it's development much more than historically was the case (and thus more like some of the advancements made in China for other reasons)?

Rockets, incendiaries, the rediscovery of Greek Fire (or it never having been forgotten), boom boom boom! All are suddenly very attractive to immortals! Armor and long bows - boooring, let's blow some stuff up!

## Maybe they can just use foul language

With physical necessity out of the way, things are going to be even more heavily culturally and emotionally influenced than they are now. If war isn't about killing, it might very well commonly be about sending a message, proving a point, taking the other guy down a few pegs, proving your groups superiority, and so on.

Suddenly insults, foul language, and other such 'psychological warfare' can take on new meaning. If sticks and stones breaking your bones can't hurt you, maybe words will!

Now go away, before I taunt you a second time!

On a meta level, war is "politics continued by other means", and politics is defined in Organizational Theory as a "means of allocating resources".

Since you cannot kill the enemy, you need to attack their will; borrowing the maxim of Sun Tsu that "Supreme excellence in war is subduing your enemy without fighting a battle".

So the question becomes how do you convince or persuade the enemy that you should have the resources under contention? Using logic, battles of wits, puzzles, appeals to emotion, deception and all the other tools and tricks that are deployed by modern PSYOPS would become the means of waging war. The Russians have used this to great effect in Ukraine and Crimea, ISIS uses it in tandem with their other tools of war and the Chinese are using this to some extent in the South China Sea. Great commanders in the past have also been able to win victories by essentially outthinking or bluffing their enemies (a good example to research is Sir Issac Brock's capture of Fort Detroit in the War of 1812).

While thinking of warfare as a form of advertising or persuasion may seem startling, messing with people's minds in the service of war is probably as old as warfare itself. Think of a Maori Hakka to imply ferocity before a battle, or the reciting of pedigree and heroic deeds by the heroes of the Iliad or Japanese Samurai prior to a battle. The analogy is imperfect (after all, you are still setting up to kill your Trojan or enemy Samurai opponent by unsettling them), but it is a good way to think of things.

Similar to the simple answer of imprisonment, you have to also catch them.

Trap

I propose a series of traps, such as the trou de loup method. A large, covered pit where they are trapped and then sealed by rocks and morter that they cannot lift or move. Keep them in there as long as you like.

• If the immortals cannot lift or move the rocks (even, presumably, given infinite time to work on the problem), then how are you going to seal the hole using those same rocks? – a CVn Sep 15 '15 at 14:15
• @MichaelKjörling - your immortals have dropped a lot of lift-able rocks onto an immortal in the trap. Once many of those lift-able rocks are above the unfortunate guy, they are no longer movable. A pile of lift-able rocks. – Mikey Sep 15 '15 at 16:52
• Right. I somehow pictured this as simply a hole in the ground, covered with rocks -- which would work until it doesn't, as the immortal could simply work their way laterally, millimeter by millimeter, by moving dirt. Hardening the sides of the hole as well as encasing the individual could make that arbitrarily difficult, simply by picking the properties of whatever materials are used. – a CVn Sep 15 '15 at 20:51
• @MichaelKjörling - good point; but by then, the war would be over, hopefully. – Mikey Jul 20 '16 at 17:47
• But would the individual who just emerged know that? Brings up a whole new set of questions, I think... – a CVn Jul 21 '16 at 6:03

I can actually think of many ways for them to "enjoy" wars, but in the long term, since they are immortal, they'd learn that wars achieve nothing.
Let me explain: if they know they are all immortal, they will probably focus on a guerrilla with ambushes and imprisonment rather than anything else. Maybe kidnapping and maybe sabotage (but hey, even if they are greedy, they can anyway live without crops, right?).
So after a couple generations the war will reach a standstill, where factions simply don't go in some territories (fear of being taken by the other faction and spend the eternity inside a volcano?).
Eventually their arrogance and ignorance (they are human-like, right?) will make some people think that they could instead reign, so I would focus more on "secret" civil wars, kidnappings and tortures rather than a proper war.

• The faction(s) that have volcanos in their territories will thus naturally emerge as the dominant factions, since they have a readily available means of indefinitely sequestering captured enemies that requires no more work than hauling them up the mountain and pitching them in! – Doktor J Sep 16 '15 at 1:34
• Well I don't think volcanoes are the only mean. Think about molten metal, cages submerged in water, use of biological means to deform prisoners and make them basically unable to live as human anymore, people frozen in ice or buried alive. I can think of a hundred ways to torture someone for eternity and make his life hell on earth... – Noldor130884 Sep 16 '15 at 6:16
• My original comment was meant somewhat tongue-in-cheek... but upon reflection probably would still hold somewhat true. Toward the dawn of this immortal civilization, before the people understood metalworking or could efficiently dig big enough holes to bury people, it would still be quite easy to haul a prisoner up a mountain and toss them into the mouth of a volcano! The tribes that had these territories would then emerge as the dominant civilizations as technology developed, and continue to retain their tactical superiority through technological advances. – Doktor J Sep 16 '15 at 16:18
• Well I get it, but unadvanced civlizations would probably fear a volcano. Digging a hole is pretty basic I think. – Noldor130884 Sep 17 '15 at 6:56

I think you have overlooked a central issue -- war by definition is a large scale organized affair. This organization in our world is motivated in part by fear of death and limited resources -- join our group or we kill you/your family/crops. This motivation will be absent from your immortals.

This will make large scale fighting organizations (armies) much harder or even impossible to form. They may do them for fun or for idealogical reasons, but consequentially will be considerably smaller scale than what we think of as war. More raids/cattle stealing/counting coup than war.

This does not totally eliminate "war" as politics by other means, it does change how it is used and the scale.

I guess it depends how many times they're willing to lose a buttock or some other body part. It would just be a staring contest

## BIOLOGICAL WARFARE would be appropriate

Expose your enemy to a hazardous biological weapon (virus) such that they lose their ability to Move.Immortality is worthless if you are paralysed.

1. Eternal imprisonment

2. Eternal pain & suffering (a real Hell)

What would be worst than that?

e.g. Phantom Zone (Superman II)

The bad guys were imprisoned in the Phantom Zone, a prison were people can never get old or die.

• Can you explain why these would be the cases? – HDE 226868 Sep 14 '15 at 23:11

I would say until weapons of mass destruction occur (say something that fully incinerates the body, say a large incendiary bomb) That most of them would turn to chess like political 'games' for 'winning' and losing. If it is almost impossible to kill your opponent, then 'other' ways will be needed to 'beat' them. I would expect a most Byzantine politics arise with an almost unfathomable score keeping to emerge. Since if violence is ineffective, other than pissing off your opponent, then it would fall by the way side as a means to an end. A show of violence, especially from an uncontroled outburst, would appear to be a childish reaction with no point or merit.

Of course, if I really wanted to get rid of one of these people because I felt they just had to go, I'd find a way to render them unconscious long enough to throw them under a lava flow. It would be the perfect prison to keep them for millenia.

Maybe one group would try to influence the other group to submit to their ways. Psychological warfare would be more damaging than actual wars in that case.

• Hi and welcome to Worldbuilding SE. Could you maybe detail how do you think that could be achieved? What means do they have to influence the others? – clem steredenn Sep 16 '15 at 10:03
• Green's answer already covered part of this. – HDE 226868 Sep 20 '15 at 13:31

In effect, Philip Jose Farmer's "Riverworld" explores a similar theme, as each death seems to be followed by reconstitution of the continuous self, elsewhere along the river.

As to the question, as in chess, or ancient Egypt, were one fortunate enough to be King, or living god.

• Could you expand on how Riverworld is significant here? – HDE 226868 Sep 17 '15 at 23:00

Make them ugly, like the Gollum in the Lord of the Rings, that should be your target. After the war, when they look in the mirror they should hate themselves.

They will fear your acid or chemical weapons which make them ugliest in the world than the 'imprisonment'. If you are imprisoning them, there is a chance for escape in a long run. But if they are ugly and loss their self identity then who will want to be immortal? So you should fight with such kinds of weapons and ideas( for example, fry them in frying pans, put them in oil and burn, inject viruses, etc.)

• Hi MoonMind. Welcome to Worldbuilding SE. What about those that are already ugly to start with? And if they can still fight while being 'ugly', then they gain a psychological advantage. Plus who says their regeneration can't recover those wounds..? – clem steredenn Sep 17 '15 at 12:06
• Thats a point..but I was thinking about ugliness caused using chemical weapons. An ugliness caused by them will be different. – MoonMind Sep 17 '15 at 16:13
• @MoonMind Right, but when they lose body mass in the future, the damaged bits will be regenerated. – HDE 226868 Sep 17 '15 at 23:00

I'm going to assume they still need to eat and drink or they'll get weak, but not die so burning and salting fields and polluting water would be a good idea, but if you want to win a war you need to find a way to stop them. Digging deep pits to throw the enemy into and then filling it with concrete or glue or even rocks would prevent them from getting out (at least for a few hundred years). I think it'd become a war of traps and capturing instead of killing.

If any are beings of honor, trapping them in a promise, a la Superman in the Frank Miller Dark Knight graphic novel.

Hurting the ones they love.

Protecting the ones they love in exchange for concession of defeat. (Or anything else that can leverage them into submission.

What happens to all of those severed immortal limbs? How many of the same head can be accumulated? (rhetorical questions).

Torture still works, even if they can't die, just ask Prometheus.

Immortals can't die. Any combat will be non-lethal. Establish appropriate rules of engagement on both sides. The soldiers on both sides line up, face to face, one on one, and play rock, paper, scissors. Which side wins the most number of rounds of the game is the victor.