Are you an alien civilization with a go-getter attitude, looking for some ripe planet to [[AlienInvasion invade]] and [[PlanetLooters loot]]? Here are some tips to ensure you don't end up like all the others out there who've [[EasilyThwartedAlienInvasion tried and failed]]. All we request for giving you this information is, should you successfully invade a planet, that you give us some of the fruits of your labor and possibly positions of power in your glorious dominion. Preferably far away from the planet we helped you invade.

If instead you want to ''destroy'' the whole place, go to JustForFun/WhyYouShouldDestroyThePlanetEarth. To learn more information from the enemy's point of view, also see JustForFun/IfIAmEverHeadOfAnAlienMonitoringAgency.


[[folder:Phase One: Motivation and Planning]]
To begin with, put some thought into ''why'' you're invading in the first place. If you're after a material good, is there an easier way to get it? Now is also the time to do some basic research on the target world in question, to make sure it's even worth the effort of conquering.
# If you're looking for some ridiculously common substance like helium, water, oxygen, etc., there are ''millions'' of lifeless rocks where you can get the stuff essentially for free, without the need to fight off pesky hostile natives. Water is the commonest compound in the universe; even if you happen to live on Tatooine, your solar system probably contains multiple Earths' worth of water in its comets alone.[[note]] Not "multiple Earths" as in "many times the amount of water on Earth"; "multiple Earths" as in "many times the Earth's ''entire mass''".[[/note]] Aluminum? Uranium? Go mine an asteroid and leave the PunyEarthlings alone.
** Corollary: Water is ''bulky''. Even a fleet of a thousand mile-wide spaceships [[SciFiWritersHaveNoSenseOfScale can't hold enough]] to make a significant impact on a planetary biosphere. [[Film/BattleLosAngeles If you need it for reaction mass]] and not to drink, see #1. In fact, if you don't need it for reaction mass and do need it to drink, also see #1 (sure, it's dirty, but you can clean it up with simple and comparatively cheap distillation--and probably get some nice salts, hydrocarbons, etc., in the bargain).
# If it's a life-bearing planet you're after, keep in mind that ours didn't evolve a sapient species until the most recent 0.004% of its existence. Given those odds, chances are pretty good that there's another life-bearing planet a similar distance away that you could easily colonise without conquering.
# If you're [[SufficientlyAdvancedAliens sufficiently advanced]] to cross interstellar space in the first place, consider investing some research into basic technologies like food replication. [[ToServeMan Harvesting native intelligent beings as cattle]] is dreadfully inefficient, and they tend to object. And if you ''are'' looking for a bite to eat, you might want to try [[AliensStealCattle abducting large, meaty animals]] instead of wasting your time with the boniest, least nutritious species on the planet --to say nothing of the only species on the planet capable of understanding what you're doing and taking exception to it. With guns.
** Corollary: If you ''do'' end up taking cattle (or sheep or pigs or whatever), you had better make sure that you either do it quietly or have indestructible ships, as farmers tend to be rather protective of their bovine (and ovine and porcine) property, and rural folk are the most likely in any country to be highly armed (particularly in [[UsefulNotes/TheUnitedStates the places]] [[UsefulNotes/{{Canada}} that]] [[UsefulNotes/{{Australia}} raise the]] [[UsefulNotes/{{Brazil}} most livestock]]). Either that, or you could trade. Even if you want to take the livestock only once and then breed them, you might want to give us some token payment in exchange for our knowledge of animal husbandry and genetics - chances are, you'll have a lot of negative outcomes with our animals if you don't have this information.
** Another corollary: Before embarking on an interstellar hunting trip, be sure to do some pretty basic biological research, such as ensuring your digestive systems are [[NoBiochemicalBarriers capable of assimilating the base molecules of which your prey are composed]]. [[MirrorChemistry Just being carbon-based ain't enough]]. Also, be sure to check that the myriad enzymes, proteins, salts and carbs floating around their systems aren't toxic to yours, and that includes in combination.
# Similarly, unless [[SlidingScaleOfRobotIntelligence your robots are really dumb]] and only sapients can do a job you can't or won't, [[WeWillUseManualLaborInTheFuture don't bother going to other planets to enslave the population]]. Better yet, buy/steal their automation technology instead! ([[FridgeLogic By the way]], [[InsufficientlyAdvancedAlien how did your species get into space]] ''[[InsufficientlyAdvancedAlien without]]'' [[InsufficientlyAdvancedAlien it?]])
** Corollary: If you insist on invading the planet anyway and your robots are ''[[SlidingScaleOfRobotIntelligence not]]'' [[SlidingScaleOfRobotIntelligence dumb]], why bother invading yourselves, just send the robots.
# Check the air and water first to make sure they aren't [[NoBiochemicalBarriers toxic to your kind]]. [[Film/{{Signs}} If you're invading a Class M planet but your species has a lethal reaction to H2O]], [[TooDumbToLive you're about to get a remedial course in natural selection]].
# Take samples of the plant, animal, and microbe life and do controlled studies to make sure your mighty invading army won't be [[Literature/TheWarOfTheWorlds killed by]] [[{{Series/V 1983}} a bacterium]]. Further, test all of these samples to ensure that they don't have [[AlienCatnip non-lethal but disabling or embarrassing effects on your biology]] like [[Literature/{{Worldwar}} ginger making your troops horny]] or [[Series/AlienNation sour milk making you drunk]].
# Cross-check your and the invadees' relative ''scale''. The only thing more embarrassing to the average galactically-feared alien conqueror than [[Manga/UruseiYatsura having your largest battlecruiser mistaken for a rugby ball and wrecked by the kicks of high school students]] is [[Franchise/TheHitchhikersGuideToTheGalaxy commanding your vast battlefleet across the interstellar void and into a screaming dive upon your target planet with all weapons blazing only for it to be swallowed in its entirety by a small dog]].
# Bring a fully-equipped scientific staff to deal with any unexpected issues that may crop up (and they will). Treat them with respect so they don't [[MistreatmentInducedBetrayal revolt on you]].
# If the [[DeathWorld air, water, or biota are hostile]], and you can't find a solution that doesn't involve covering your people with inch-thick environment suits, ''leave''.
** Corollary: If the ecosystems are hostile but you're after something underground, consider burning the offending biospheres off with an orbital bombardment. Your guys will still be in life support suits, but you'll save money on security.
# Study the history of your target planet - you shouldn't even need to make contact for this as any planet technologically advanced enough to be a threat to you is going to be broadcasting information like crazy. If they've got a history of thwarting invasions and bringing unstoppable galactic juggernauts of destruction to heel, you'd better be damned sure you know a few tricks the other saps didn't. If not, and you have sufficiently skilled diplomats, consider just asking for whatever it is you want. Maybe you can even offer the natives a big enough bribe and [[HumansAreWarriors point them at your enemies]].
** Caveat 1: if the inhabitants of your target planet appear to possess [[RuleOfCool implausible levels of martial prowess]], be sure that the information you're observing [[AliensStealCable is non-fiction]].
** Caveat 2: if the inhabitants of your target planet are technologically advanced enough to pose a threat to you and also apex predators, expect anything and everything to be something they can figure out how use as a weapon against you.
** Caveat 3: don't feel like you're going to have an easy time just because you have a species of pacifists or at least very peaceful people on your hands. If they have a pretty warlike history, you can be sure that at least some of the old fire is still burning and they are probably only restrained by their luxuries. If you are unlucky, they all turn into Klingons as soon as you take their luxuries away from them and give you hell.
# Before you even start shooting, study the native technology to make sure that your super-advanced weaponry isn't [[CoolButInefficient startlingly]] [[AwesomeButImpractical inferior]] to its [[RockBeatsLaser mundane equivalent]].
** Corollary: ''Never'' underestimate the enemy's ability to [[StarWars improvise]].
** Second Corollary: Analyze their technology from every possible angle. Is there anything seemingly harmless that [[SuperweaponSurprise could be used as a powerful weapon]]? Be sure not to overlook [[WeaponizedExhaust easily-weaponized non-weapons technology]] when making a threat assessment! (See those [[Literature/KnownSpace big cats]] over there? Ask them about this one; will ''they'' have stories to tell). Keep in mind that [[ProudWarriorRaceGuy depending on]] [[HumansAreWarriors the species]], an effective LotusEaterMachine and an [[IKnowMortalKombat advanced military training simulator]] may turn out to be [[WarriorHeaven the same thing]].
** Third Corollary: Don't be too proud to steal ideas. If it works well against you, it might work well against others.
# Learn your TechnologyLevels! Even in with all the {{Alternate Techline}}s out there, knowing in general what stage of development a planet is in will be essential for a successful invasion; especially when identifying technology that has been supplied by rival stellar civilizations. Natives of a planet that's on the verge of [[FasterThanLightTravel FTL travel]] and those who have just discovered flint knapping will each have [[NoSuchThingAsSpaceJesus very different reactions]] to your presence.
** Corollary: Once you've gotten an idea of what the natives are like, ''never'' make assumptions of how rapidly they'll advance between now and the invasion. If you come to a planet [[Literature/{{Worldwar}} assuming that they'd still be wielding sticks]] and they're actually developing the atomic bomb, you're in real trouble. [[TabletopGame/{{Warhammer 40000}} Especially if they are now arguably more advanced than you]].
** Second Corollary: If the species of the planet you are attempting to invade has developed FTL travel, don't even bother. You could risk losing most of your invading force, [[Literature/EndersGame opening up yourself to invasion]], [[Franchise/MassEffect upsetting your neighbors]], [[VideoGame/SwordOfTheStars or causing a galaxy-spanning war that could result in them exceeding you technologically]].
** Third Corollary: If your research is performed from a distance such as your home planet using high-powered telescopes, the light patterns you see will be as they were when they were projected from the alien planet. If you are doing your recon from two hundred light years away, even if your travel time was zero, the data would be two hundred years out of date.
# ''Secure your damn computers.'' This gets brought up in other phases, but it cannot be emphasized enough. Don't leave your home planet until your MasterComputer is good and damn protected [[Film/IndependenceDay against any intrusion attempt (no matter how unlikely)]] and your mothership is staffed with competent IT personnel among your underlings to make sure it stays that way. And treat them like goddamn royalty, General, because they'll be what keeps you and your invasion fleet alive and intact to finish your conquest.
# Once you have a clear idea of the life forms you intend to subsume and of their culture, now is the time to do some ''very'' intense politicking. No truly sapient race, [[AliensAreBastards no matter how inherently violent,]] is composed entirely of ravaging, bloodthirsty monsters. [[KlingonScientistsGetNoRespect Someone has to do the bookkeeping and keep the libraries running.]] Even your [[WesternAnimation/StevenUniverse best and highest ranking soldiers]] might have qualms about exterminating all life on the target planet, and some, should the invasion take place, [[Film/{{Avatar}} might even go native]]. Before you begin your expedition therefore, it is absolutely vital that you get your entire population on side. [[PropagandaMachine Propaganda]] is the best method of achieving this, particularly portraying your targets as ravaging, bloodthirsty monsters. If they are [[HumansAreTheRealMonsters anything like ourselves]], that shouldn't be too hard.
# If your plan is to {{terraform}} the world into a climate or environment more suitable for your own kind, once ''again,'' step one is to see if some uninhabited rock will do. If you're ''sure'' it won't, then exterminate the aboriginals before commencing operations - you'll be destroying their civilization regardless, and aboriginals are often shockingly adaptable and determined to survive terraformation.
# If your plan is to, by one means or another, {{terraform}} the planet ''[[HostileTerraforming before]]'' [[HostileTerraforming you arrive]], take the time to scan the hopefully-hospitable planet before approaching. The [[VideoGame/CommandAndConquerTiberiumWars locals may have interfered with the terraforming process]], and at least a few have probably survived, and if - or more likely, ''when'' - they figure out you were responsible for [[TheEndOfTheWorldAsWeKnowIt the end of the world as they knew it]], they will be ''pissed''.
# If you are biologically compatible to any degree with the aboriginals, even if it's just being able to consume one another's flesh for nutrients, then make sure not to ignore the issue of germ warfare. Send robotic or [[WeHaveReserves expendable]] scouts in first to collect samples (see the abduction recommendations in the Meeting the Locals section for details), and run a thorough vaccination program on anyone who will come into contact with the natives.
** Corollary: try infecting the local population with a disease that your own people are either mostly immune to or only mildly inconvenienced by, preferably after inoculating your own troops against the indigenous pathogens to avoid a massive backfire. If you're lucky, their population will be devastated and their civilization in utter chaos, making conquering quite easy and leaving large swaths totally unoccupied.
# If your civilization is trying to recover a piece of LostTechnology last seen in this sector of space, always, ''always'', '''''always''''' assume that the natives have found it, reverse-engineered it, or know how to use it, and plan accordingly. If you believe that your invasion will be utterly destroyed if the natives use this technology, just don't bother.
# Check out the enemy planet for signs of an [[JustForFun/IfIAmEverHeadOfAnAlienMonitoringAgency Alien Monitoring Agency]] '''BEFORE''' you invade. If they have a GenreSavvy [[JustForFun/IfIAmEverHeadOfAnAlienMonitoringAgency one]], don't bother. If however the agency is non-existent or is AHalfDozenGuysInABasement, you may be okay. If one of its agents is a certain [[Series/TheXFiles Fox Mulder]], your chances are about 50/50: although [[AgentMulder he knows exactly]] ''exactly'' what you're doing, there's a good chance [[CassandraTruth nobody will believe him anyway]].
# If you have an insatiable desire to eat souls, have you considered manufacturing them? Souls are software objects: investing in the mass simulation of innocents is both cheaper and safer than eating out. [[note]]Call Microserf for a meeting in your star system.[[/note]]
# You may think it brilliant to simply [[TimeTravel go back to an earlier time in history]]; before your target victims [[Franchise/StarTrek discovered warp-speed, phaser guns, and teleporters]], and the height of their technology are [[Franchise/TheHitchhikersGuideToTheGalaxy snazzy digital wrist-watches]]. Just remember, chances are you won't be the only one trying to alter history. And folks won't be pleased that you're trying to destroy their ancestors. In addition, be aware of the tendency of primitive civilizations to have access to magic. Nothing breaks morale more than having half your fleet taken down by a wizard on a hill.
# Look into [[AllMythsAreTrue native legends and myths]]. If they indicate that your intended conquest has an [[Series/DoctorWho alien protector]], a [[Series/StargateSG1 secret military unit that has already made contact with far more advanced alien species and defeated them by employing guerilla tactics]], a [[Series/{{Torchwood}} stockpile of alien artifacts]], or some other [[SealedGoodInACan recurring righter of wrongs]], you may want to look elsewhere.
# Similarly, keep a constant watch for: [[Series/DoctorWho a small, innocent-looking blue box]], [[Franchise/StargateVerse covert military units with "SG" in the name]], [[Anime/TengenToppaGurrenLagann mecha sporting]] CoolShades, [[Franchise/StarTrek saucer-shaped cruisers]], [[Franchise/SuperSentai giant]] [[Franchise/PowerRangers robots]], [[Film/MenInBlack well-dressed men in sunglasses]], [[VideoGame/SwordOfTheStars starships with ring-shaped FTL systems]], [[SuperHero vigilantes in colorful costumes who casually defy the laws of physics]], [[Franchise/{{Metroid}} a power-armored warrior with huge spherical shoulders]], or [[Franchise/{{Halo}} anyone in power armor]], even if they're [[VideoGame/HalfLife bespectacled physicists]] with [[WeaponOfChoice crowbars]]. Spot any of these and you're better off staying home. While you're at it, also check for [[Franchise/{{Transformers}} any uninvited guests masquerading as local machinery]]; such party-crashers usually have drama of their own, and you do not want to get sucked into it.
** Exception: If you think you can trick the governments of the world into doing something [[MoralEventHorizon horrific enough to cause this guardian to turn away in shame]], you might narrow your opposition down to [[Series/{{Torchwood}} some Welsh bisexuals]]. Still a tough fight, but it's better odds. Alternatively, if the protector works secretly, see if you can expose them without tipping your own hand; the natives may deal with your problem for you.
** However, if the protector is [[WesternAnimation/MegasXLR a fat guy from Jersey piloting a giant robot with a car in place of a head]], then ignore the exception and move on. No, not even to make friends with him; [[DestructiveSavior he's just as dangerous to friends as he is to enemies.]]
# If, after conducting intensive scans and careful research, you find that there is no protector on the planet...don't move forward with your invasion just yet. Gather intel from the other alien empires in the galaxy, first. If one of them's getting torn apart by a single individual or a small group of individuals hailing from the planet you're orbiting, call off your invasion plans. You've just found this planet's protector.
# At the end of the [[ExpospeakGag Planetary rotation period]], your best bet may be to remember [[Series/StarTrekDeepSpaceNine Rule of Acquisition #35]]: "Peace is good for business." It's much cheaper in the long run to [[JustForFun/AbusingTheKardashevScaleForFunAndProfit trade]] than to invade. Many planets even practice slavery, and they certainly will like your new technology. Just remember to trade them microwave ovens, not death rays (and you may even want to rethink giving away that microwave oven tech, unless you fancy the risk of being toasted with MASER weaponry). If you use this route, remember to keep your deals square. Otherwise you'll face a threat worse than any armored or caped or scarfed hero: ''[[EvilLawyerJoke lawyers]]''.

[[folder:Phase Two: Meeting the Locals]]
You know why you're here, and you've arrived. Now it's time to say hello to your future conquests and build goodwill and trust you can later betray.

If subtlety isn't your thing, feel free to skip on to Phase Four: Conquering the Locals. Alternatively, if you wish to remain hidden while infiltrating the natives' society, skip to Phase Three.
# If you [[WeComeInPeaceShootToKill don't come in peace]], don't even bother and just start invading (see Phase Four). Any time you spend learning about and infiltrating ''them'' via subterfuge and public relations is time you are giving them to learn about ''you'' and your weaknesses and limitations via spying, ill-conceived dropped factoids, and basic behavioral habits.
# If you decide to go through with this step, expect the locals to speak a ''[[StarfishLanguage very]]'' different language from [[IndoEuropeanAlienLanguage yours]]. There will have to be a [[ArtisticLicenseLinguistics great deal of time invested in decoding and learning]] it well enough to establish diplomatic relations.
# Hire a really good cultural interpreter to help you get around those [[EitherWorldDominationOrSomethingAboutBananas unfortunate misunderstandings]] that occur when you are dealing with [[StarfishLanguage alien languages]] and customs. It really damages any occupation attempt when the first thing thing the locals hear you say is [[MyHovercraftIsFullOfEels how your hovercraft is full of eels]] rather than how your spacecraft is full of orbital-bombardment cannons.
# Don't remark on how [[HumansAreUgly ugly]], short, tall, overlimbed, underlimbed, [[PunyEarthlings weak]], [[HumansAreMorons stupid]], [[HumansAreSmelly stinky]] or [[EnergyBeings non-spectral]] the natives are (at least not in public) as it's never a good thing to insult the hosts. [[BlueAndOrangeMorality Well, most of the time, anyway.]]
# Don't pretend to be "[[IWasJustPassingThrough just passing through]]" when you have clearly studied the native culture well enough to look exactly like them, speak the language fluently, and understand their societal and cultural issues.
# Helpful hint: appearing out of nowhere [[Film/IndependenceDay over dozens of cities at once in giant ominous spacecraft]] is not good for public relations. Figure out how the natives communicate and [[IComeInPeace talk to]] [[TakeMeToYourLeader their leaders]] a bit first. Give them time to prepare for the culture shock.
# Don't try to look too much like the natives. [[HughMann Uncanny resemblances]] breed suspicion. Unless there's some kind of weird universal [[HumanAliens convergent evolution]] going on, in which case ''explain this ahead of time''.
# If you are really [[{{Series/V 1983}} reptilian monsters]] underneath those disguises, have a contingency plan for when the natives figure this out. Better yet, come as yourselves. The natives will get over it faster than if they find out you're hiding something.
** Corollary: The great thing about being up front about your non-nativeness is that no one will ever imagine you can use spies, moles, saboteurs or [[Series/BattlestarGalactica2003 sleeper agents]]. Won't the natives be surprised when anyone from the janitor to their [[TakeMeToYourLeader supreme leader]] [[TheyLookLikeUsNow can be one of you?]]
# Don't try to lure the natives with the [[InterspeciesRomance promise of sex]]. Sooner or later they'll actually want some and; (a) figure out you can't provide; or (b) do it and end up giving birth to some weird HalfHumanHybrid with magical powers that will be turned against you.
# If [[MarsNeedsWomen the natives are attractive to you and there are enough genetic and physiological compatibility factors to make mating feasible,]] win them over by offering them a life of leisure, luxury, and pampering. Do not attempt to abduct and [[SexSlave sexually enslave them]] - neither they nor their mates will appreciate that very much.
# Don't try to supplant the natives' religion. It never goes well. Instead of friendly natives, you'll end up with a bunch of mindless grovelling sycophants, a bunch of violently outraged fanatics who will stop at nothing to kill you, or both.
# If you're sending scouts down to the planet, make sure none of them are the type to [[Film/{{Avatar}} sympathize with the natives]] and either [[DefectorFromDecadence defect]] or [[WesternAnimation/BattleForTerra sabotage your plans]].
** Corollary: don't mistreat or kill your own workers. They will defect and they will tell the natives exactly how to crush you.
** Exception: if your civilization is congenitally racist and even the lowest peons regard themselves as better than all other species, you might have a bit of leeway. But be warned, sometimes they can go soft on you and start empathizing with the native animals.
*** Remember, robots are physically incapable of disobeying you if you [[AIisaCrapshoot program them right]]. Use them to scout instead.
# If normally objective scientists suddenly claim an ostensibly supernatural phenomenon, such as [[Film/{{Avatar}} the natives' version of God]], is both real and scientifically verifiable, do not dismiss them out of hand, no matter how much easier ignoring it would be. Halt all operations that might be affected, have their results verified by independent scientists, and tested by another group of scientists, with full procedures observed as much as possible. If they are correct, modify or cancel operations accordingly. Unless you're feeling confident that your death rays work on deities.
# Don't forget that {{Cargo Cult}}s can spring up even if you don't attempt a GodGuise, so be prepared to remove all traces of your presence on the planet if you plan on leaving it for an extended period of time. Otherwise, SocietyMarchesOn and all it takes is one {{genre savvy}} anthropologist to connect the dots, leaving you with a significantly lower reputation as [[AliensAreBastards alien bastards]], instead of the more ideal status of [[FirstContact "first" contact]].

[[folder:Phase Three: Infiltrating the Locals]]
Phase Two is complete, and the natives are now convinced of your good intent and benevolent nature. Suckers. While you keep the public relations campaign going, now's the time to get to know these saps a little better through quiet abductions and vivisections, while your agents worm their way into positions of power.

If all goes as planned, you can skip ahead to Phase Five once you're done.
# If you wish to [[PlayingWithSyringes "learn"]] about the anatomy/biology of the locals before destroying them (and still wish to remain hidden), make sure you abduct specimens who either won't be missed or won't be reported missing, i.e. a homeless local or someone who lives in the middle of nowhere.
# Unless you implant some sort of MindControl device into the specimen without killing them, never, ''ever'' release them back into the general public if you don't want your cover blown. Although, depending on the species, the others may or may not believe the abductee. [[WhatCouldPossiblyGoWrong It still doesn't hurt to not]] [[TemptingFate take a chance.]]
** Also, be ''absolutely certain'' that the abductee isn't an associate of a future LaResistance leader and/or member. Warning signs are if male abductees are skilled enough in all forms of combat to make abducting them in the first place problematic, or if female abductees are irresistable to young male members of their species.
** It may be easier to steal (or even purchase) some of the native's own studies on their biology, they've spent much longer than you learning their own anatomy.
# Any infiltrators should be closely monitored for defection. Should there be strong or conclusive evidence of such, they should have their security clearance revoked ''immediately'' and be detained in a holding facility, preferably far away from the target planet, ''not'' guarded by anyone they could ever possibly have met, and certainly not anyone sympathetic. And by ''immediately'', we mean "have that changed in the system ''now''." [[Series/BabylonFive Just because you took away their key- and identification cards does not mean that they don't have another stashed away somewhere]].
# If your goal is to [[PuppeteerParasite take over the natives' bodies]] [[Literature/{{Animorphs}} to use as your own]], then your ''entire'' invading force is [[TheMole Moles]]. You are in the perfect position to conquer without anyone even knowing you're there until it's too late; overt acts of conquest, however, ''[[Literature/{{Animorphs}} Esplin 9466-alpha]]'', will just alert the natives to your presence and get them to mount a defense/resistance. On the other hand, you're in an ideal situation to use a [[HumansAreWarriors sufficiently xenophobic and violent]] host species to do the dirty work of eliminating your interstellar enemies for you.
# Don't try to break up the inevitable LaResistance with heavy handed police state tactics. Ignore them -- if your {{Masquerade}} is good enough, nobody will believe them.
# If you are planning to take over a planet ''without'' a [[OneWorldOrder unified global government]] (such as Earth), you may consider a great alternative to a direct invasion: {{proxy war}}fare and {{divide and conquer}} strategies. [[PlayingBothSides Manipulate various factions and set them against each other]]; exploit existing geopolitical conflicts between different nation-states. If the ultimate result is a {{world war| III}} that destroys all major military powers, the natives will have done most of your dirty work, leaving you with the chance to seize what's left of their former civilization.
# If for [[TheMasquerade some reason]] you [[Literature/{{Animorphs}} can't identify the defenders]], don't waste too much time on fruitless hunts for them, go ahead with the invasion and carpet-bomb LaResistance's area of operation.

[[folder:Phase Four: Conquering the Locals]]
Maybe subtlety isn't your thing. Or maybe your covert operations have been exposed and the natives are starting to fight back. It doesn't really matter, because you've just entered the most entertaining phase of your invasion!
# Weigh your advantages. Arriving from space, you will have control of the single greatest field of battle imaginable. No point on the planet's surface will be closed to you, and none will be more than a few hundred miles away. Additionally, if the world you're invading is anything like our own, it will have laws in place ensuring that no space-based weapons exist to impede you, precisely because no one wanted to be the first country subjected to the same attack you are now attempting. On the other hand, space is VAST, and the field of view is essentially unlimited. Unless you have access to some kind of instantaneous FTL jump technology, your victims, if they possess a technological level beyond that of the Middle Ages, will have prior knowledge of your arrival, if not of your intentions.
#If your chosen planet is unfortunate enough to be cursed with [[ a large natural satellite in a state of tidal lock with itself]], consider hiding a portion of your forces behind it. If they arrived snug in the mothership, your future subjects will never see them.
# If the heavier elements of your invasion fleet [[VideoGame/XCom have to arrive later due to logistical problems]], '''Wait'''. Do not waste precious troops sending down your scout forces to be annihilated and give the locals opportunities to study your race.
# All of your troops should be reminded that they have orbital superiority. The best direction to retreat is ''up''.
** Corollary: The best direction to attack is ''down''. Don't risk your [[Film/IndependenceDay city destroyer]] unnecessarily by moving it in a straight line nor having it [[OminousFloatingSpaceship hover above the target even after it has razed it to the ground]]. [[RuleOfCool It looks cool]] but [[AwesomeButImpractical offers zero tactical benefit]].
# [[EliteMooks Special forces]] should be used to eliminate targets of strategic importance, operating ''alongside'' or ''before'' the main invasion force. They should not be sent in as a last resort.
# If your objective is to conquer the planet and KillAllHumans, just ''do it''. Don't beat around the bush -- if you've traveled across light-years to get here, you've gotta have some pretty decent weaponry. The longer you wait under the [[WeComeInPeaceShootToKill pretense of being friendly]], the longer the natives have to organize a resistance and find your weaknesses... or [[SummonBiggerFish call for help]].
** Corollary: If you are going to KillAllHumans, damn well finish the job. Those scattered bands of pitiful survivors may look pathetic and harmless ''now'', but give them a few generations to build up their numbers and you have a bunch of [[Literature/BattlefieldEarth determined]], bitter opponents who are very good at not dying.
** Second Corollary: If your interest is not specifically in wiping out ''only'' the dominant race, consider [[DeathFromAbove orbital]] [[ColonyDrop kinetic]] [[ApocalypseHow bombardment]] that will reduce your target planet to, at best, a blasted wasteland and at worst a pile of molten slag.
** Third Corollary: If your foe has weaponry that can menace your ships and/or you've come ''too'' late and they've expanded across their star system, use if you can the comparatively low-cost approach of [[Literature/TheKillingStar accelerate a good bunch of robot-controlled asteroids and/or obsolete ships at relativistic speeds and smash them against their worlds]]. They'll have very little or no time of warning.
** Fourth Corollary: If you plan to fire on natives on foot with your ships' weapons, make sure you equip your ships with antipersonnel weapons and targeting systems precise enough to hit a moving target the size of a grape. Mortars and missiles with similar targeting systems should also be considered for when natives run in a straight line directly away from one of your attack ships as a group.
# Rig any of your technology that the natives could possibly capture with a [[FailsafeFailure foolproof]] remote-controlled [[SelfDestructMechanism self-destruct mechanism]]. Your technological advantage in combat exists only as long as you and your allies are the only ones using said technology.
** Corollary: Make sure the enemy is not skilled in HollywoodHacking first. Nothing quite compares to your invasion force dramatically exploding moments from final victory.
** Second Corollary: Make sure that you have an override code to execute this destruct in the event your people try to use the equipment they were issued against you.
** Third Corollary: Even if your self-destruct mechanism is foolproof, don't get overconfident. [[VideoGame/XCom If the enemy gathers enough of those fragments, they may still be able to reverse-engineer your weapons]].
# Make sure your infantry weapons don't have [[BottomlessMagazines infinite ammunition]]. If the natives capture them, it will come back to haunt you. The best course of action is (if you can give them bottomless magazines in the first place) to use [[Film/{{District 9}} gene-locking to limit them to your troops]].
# If your invasion armada has [[TheMothership a mothership]], make sure it's indistinguishable from the rest of the fleet, [[KeystoneArmy doubly so if its destruction would disable your armed forces]]. And give it decent enough telecommunications to stay in orbit where it can't be taken out by [[VideoGame/StarCraft a dozen grunts with assault rifles]].
** Corollary: Expect the best native tactician to [[Literature/EndersGame spend hours studying recordings of your maneuvers]] searching for weak points. You mothership should not be recognizable even under this level of scrutiny.
** Second Corollary: If you absolutely ''have'' to have an ostentatious mothership, have at least one class of ship that is bigger and more obvious, or make it part of a regular class of ships. To many civilizations, BiggerIsBetter is usually an indicator of major firepower or command, and will tend to focus efforts on them.
** Third Corollary: A single small ship hanging back from the main engagement is ''also'' an obvious target and therefore a bad place to command your operations from, especially since actions against it will tend towards using a RagtagBunchOfMisfits who may well be more effective than the regular enemy force.
** Fourth Corollary: Maybe you should go ahead and give your mothership, and the rest of the fleet, your finest [[CloakingDevice stealth technology]].
** Even if you intend to follow all corollaries to the letter, do have a backup plan in case your mothership is destroyed anyway, and make sure the invasion can proceed even without it. If its destruction would indeed [[KeystoneArmy disable your armed forces]] treat this as the biggest flaw in your plan and halt all invasion preparations until it's fixed. Otherwise no matter how many precautions you took and how many advantages you have to balance this one weakness out, you are TemptingFate.
# Put a firewall on your MasterComputer so they can't disable your DeflectorShields [[Film/IndependenceDay with the Melissa virus]]. Enemy hackers will try to [[HollywoodHacking break into your computers]] and destroy them with a ComputerVirus. Sometimes it's because [[ETGaveUsWiFi their technology was reverse engineered from yours]], and sometimes... [[MagicalComputer well, sometimes they just get lucky]].
# If an older model scout ship that you lost contact with decades ago suddenly shows up in the middle of your invasion and wants to dock with your mothership, don't let it. Quarantine it and make sure that it's not the natives [[DressingAsTheEnemy pulling some trick on you]]. In fact, [[NoNonsenseNemesis just shoot it]]; even if it ''is'' the pilot that was shot down, they've probably either gone native or developed Stockholm Syndrome by now. [[YouHaveFailedMe Plus the guy was dumb enough to get shot down in the first place]].
# If you are the kind of aliens who prefer to seed planets with TheVirus rather than land and conquer, when you do follow up in person, don't just [[WhatCouldPossiblyGoWrong assume that your virus worked perfectly]] and [[TooDumbToLive come without any kind of defenses]].
# If the only threat to your rule is isolated or tied down somehow to a single geographic area such as a city or country, ''take care of them last'' - get entrenched first. Conquer everything out of their range of protection first, then lay siege to the remaining area. Use your now-superior amount of the planet's resources to overpower them with sheer numbers ''and'' superior weapons. Both, not either.
** Addendum: Some particularly [[VideoGame/HalfLife2 hardy specimens]] will continue with guerilla warfare even after this point. Carpet-bomb the area when you've got him pinned down. Try rodding them first, so you can go in immediately afterwards. If you have sufficient quantity and shielding, try using free-neutron emitters. If either of those don't work or are unavailable, ''then'' go to [[NukeEm nukes]]. Preferably from orbit. After all, it is the only way to be sure.
# If you do end up having to fight LaResistance, consider using your advanced technology to build some decent, reliable ranged weapons. [[NeverBringAKnifeToAFistFight Hand to hand combat]] is ''so'' last century, and the natives will probably [[ZergRush outnumber you]]. Exception: If [[DeflectorShields shield]] technology has developed [[Franchise/{{Dune}} in such a manner that only slow objects can penetrate them]], [[GunsAreUseless guns are, of course, useless]], and you may freely ignore the above advice. However, [[Literature/{{Dune}} should there be situations where the enemy is not using/cannot use shields]], be sure to have ranged weapons in reserve.
** If you have such shields, make sure that [[Series/StargateSG1 a thrown knife is not slow enough.]]
# Don't commit your entire force to the first wave. Keep reserves, including your high command, at a safe distance. If the natives are pushovers, you haven't lost anything. If they're tougher than expected, you've got TheCavalry to turn the tide. If they find an AchillesHeel, the second wave can figure out how to counter it. If all else fails, [[KnowWhenToFoldEm you've got a way to retreat]].
# Recall that [[{{Planetville}} a planet is not a city]], and thus any attempt to conquer one [[SciFiWritersHaveNoSenseOfScale is roughly equivalent to a world war and not a small battle]], and that planets, unlike cities, can be and usually are entirely self-sufficient. Make sure that you have either sufficient technological superiority/firepower to render any of the natives' numerical and logistical advantages useless, or get yourself a billion-soldier army, a million-man planning department, and get ready for several years of potentially fruitless hard slog.
** In the same vein, you cannot hope to invade a planet with five (or god forbid, ''one'') FlyingSaucers. No matter how many cities a single one can take or how much a single one of your troops outmatches the locals, you have no hope of occupying the planet.
** If you are the remnants of a scouting or invading force that arrived without the rest of the fleet for some reason, ''radio home for backup''. Do not attempt to take on the entire military might of the locals by yourself.
# Remember, just because you've [[SpaceBattle destroyed the defending fleet in orbit]] doesn't mean you control the planet: "You can bomb it, you can strafe it, you can cover it with poison, you can turn it into glass, but you don't own it unless your infantry's on it and the other guy's isn't." In other words, despite your victory in the void, you probably don't have a single boot on the ground; the planet is thus still entirely in the hands of your enemy, and therefore ''not'' conquered and still hostile. Now you have do decide: Do you even want the planet? If so, do you have to keep the surface intact and the natives alive? If you think that the answer is "yes" to either question, see immediately above. Is it worth it given the cost? (Don't succumb to the SunkCostFallacy!) If you don't want it or if the cost is too high, just bombard it from space [[VideoGame/{{Homeworld}} before the locals send their stockpile of ICBMs your way]].
# Make sure you didn't [[VideoGame/UniverseAtWar wake up other alien groups]] while duking it out or provoke feint attacks. If the planet is capable of supporting carbon lifeforms, there's the potential of precursor civilizations coming and starting a two-way war with you.
# Similarly, beware alerting any sort of Intergalactic SpacePolice, especially an [[TheChosenMany elite]] [[GreenLantern stateless one handpicked for their ethics and fearlessness]] with the imagination to use their standard [[ImaginationBasedSuperpower wonder weapon]] to maximum effect. Sure, you might be able to take out the local opposition, but can you do it before they can call for [[TheCavalry backup]]?
# Just because you ''can'' build the [[Franchise/{{Alien}} perfect combat organism]] or biological weapon capable of wiping out entire civilizations doesn't mean you ''should''. It could just as easily turn on you and wipe you out.
# Make sure your fighter ships have weapons and targeting computers accurate enough to hit a moving target the size of a grape. Then have your pilots practice hitting those targets with those weapons at different distances and under a variety of circumstances. This is right out of the Evil Overlord handbook; you want your forces to be able to hit a moving native target at range.
** Further instruct your pilots not to waste laser power if a single native is running in a straight line directly away from their ship. Give that targeting computer the few seconds it needs to confirm a lock, THEN fire the lasers. If it's a group of natives fleeing together in this manner, switch to high-yield missiles and weapons with a large area of effect.

[[folder:Phase Five: Ruling the Locals]]
The dust has settled, most of the fires have gone out, and your new subjects are getting used to the fit of their shackles. It's good to be the king. To ensure that you ''remain'' the king, keep reading.
# The indigs have been figuring out how to govern themselves for longer than you, and have probably come up with some [[EvilOverlordList helpful]] [[Literature/ThePrince suggestions]] on how to do so. In other words, ReadTheFreakingManual.
# For Xenu's sake, if you ''have'' conquered the populace, [[Film/BattlefieldEarth don't take one of your enslaved locals to a preserved library full of technical manuals, scientific journals, treatises on military history, and inspiring historical documents]], [[JustBetweenYouAndMe just so you can gloat about how none of it will help them]]. They always seem to stumble upon their version of the Declaration of Independence, and then you might as well just bring out the white flag.
# If you keep any of the locals alive, don't tell them ''anything'' about you, or ''especially'' your technology. Even if it's for one of your [[ZanyScheme intricate and excellently thought-out plans]], or you feel like gloating, or if you plan on killing them afterward. There's just too much potential for things to go wrong.
# For that matter, don't take the aboriginals as [[Literature/BattlefieldEarth slaves or pets]]. They may look cute and/or harmless, but it's just not safe in the long run.
** On the other hand, providing good living conditions, health care, and good pay (in currency worthless to you) can work quite well so long as your own people don't have obviously superior living conditions. As slaves, aboriginals are nothing but trouble. As "valued employees," [[Literature/KnownSpace aboriginals may prove surprisingly useful]].
# ''[[Film/BattlefieldEarth Pay attention]]'' to your conquered territory. If you're not going to administer it yourself, at least garrison it with your own people. [[VideoGame/StarControl Assigning one set of slaves to keep an eye on another]] is just asking for trouble. If you can't spare anything but a surveillance drone, at least be smart enough not to put it on a predictable schedule.
# Use [[TheQuisling quislings]] well. They work great for putting a native face on your policies, and sapients take orders better from their own kind. Some native will be willing to help the occupation in exchange for luxury for their family and very little real power.
# At the same time, keep a close eye on any [[TheQuisling turncoats]] that have joined your side. If they're willing to betray their own species, their words of loyalty aren't worth squat; [[RewardedAsATraitorDeserves reward them appropriately.]] [[ReverseMole And some of them aren't really working for you at all.]]
** On the other hand, don't ''entirely'' distrust your turncoat lackeys. They can be used to [[VichyEarth mask your rule with a "local" face]]. The more you keep the same under your rule as when the planet was independent, the less the locals will even notice that you're there, and the more likely they'll dismiss LaResistance as paranoid lunatics.
# While brutal dictatorship is the most obvious and well-tested method of governing an occupied planet, have you considered [[Literature/BraveNewWorld unlimited freedom to indulge]] in [[WesternAnimation/WallE consumption]], booze, [[GovernmentDrugEnforcement drugs]], [[EternalSexualFreedom sex]], food, gewgaws, games, [[SillyLoveSongs idiotic music]], and [[BreadAndCircuses other forms of entertainment]]? ([[TVTropesWillRuinYourLife Internet access is particularly good for this purpose]].) Even if it doesn't turn out to be cheaper than your SecretPolice, it will pay off by ''utterly pacifying'' the populace, who will be so busy buying, eating, drinking, playing, and [[PrecisionFStrike fucking]] that the few people who might have the will to stand up against your regime will be a couple of scattered, self-righteous, egghead intellectuals. If you play your cards right, [[Literature/BraveNewWorld even they will be at a loss at how to overthrow you, consoling themselves with simply being unhappy as a small act of rebellion]].
# Even if your technology can cover the entire planet [[SciFiWritersHaveNoSenseOfScale (a dubious proposition in of itself)]], don't erect just one of anything that could be important to maintaining your control of the planet. Revolutionaries might be able to disable ''a'' [[EarthShatteringKaboom planetary bomb]] or MindControl device, but taking out three hundred and twenty-one of them worldwide requires much more effort and gives you fair warning if the apes can actually pull it off.

[[folder:Phase Six: Worst-Case Scenarios]]
Seriously? We made you this guide and you still... all right, stop panicking, let's see if we can salvage this fiasco.
# If you are not really strong enough to conquer the planet, but are instead faking superiority in order to hide a WeaksauceWeakness or AchillesHeel, have a plan for the natives figuring this out. Even if it involves begging for mercy, it's better than ''dying''. Who knows, they might even help you willingly.
# If there's a stronger alien race out there that you're fleeing from because they are [[AlwaysABiggerFish even nastier than you]], ''don't'' [[VideoGame/SinsOfASolarEmpire go out of your way]] to [[VideoGame/{{Iji}} antagonize the natives]] if there's [[Series/{{V 1983}} any chance]] ([[VideoGame/XCOMEnemyUnknown or potential]]) [[Franchise/JusticeLeagueOfAmerica that they could help you]]. ''Do'' [[Series/EarthFinalConflict befriend and equip]] the natives for the inevitable conflict so that they'll be on your side by default, because if you don't the other aliens likely will. And if you show up [[Series/FallingSkies late to the war]], share your tech with any rebels.
# If there's [[VideoGame/UniverseAtWar a stronger alien race out there that you're fleeing from because they are hunting you down]] for the [[HordeOfAlienLocusts planet-looting vermin]] that you are, finish your work quickly before they show up and [[EnemyMine recruit the natives to their side]]. Don't count on your PropagandaMachine working.
# If, despite all your preparation and technology, you're losing the invasion, be sure to wipe your starmaps. The last thing you want to do is give those little bastards directions to your homeworld so they can [[Literature/EndersGame launch a punitive invasion]]. Do this the '''instant''' you detect a [[Franchise/{{Metroid}} visor-shaped starship]] in your immediate corner of the galaxy; its spherical-shouldered pilot has a tendency to make planets explode, and the longer it takes her to find yours, the better off your empire will be.
# If you are forced to cut your losses and call off the invasion, make sure you either take all your technology with you when you leave or at least set everything you have to leave behind to self-destruct. Not only is leaving advanced technology in the hands of a lesser species bad form, but it'll come back to bite you in the ass when they figure out how to travel beyond their solar system.
# In case of complete rout and really serious worst case scenarios, make sure you have a [[StarWars Death Star]] on hand or have [[VideoGame/{{Spore}} bought a planet buster from a friendly empire]]. Sometimes you just have to cut your losses, accept that you can never conquer Earth, and [[EarthShatteringKaboom just blow it up]]. Of course, watch out for [[RagtagBunchOfMisfits small groups of plucky heroes]] in or out of spaceships - because those guys will always manage to blow up your Big Death Thing.
# Above all else, ''KnowWhenToFoldEm''. Know when to walk away. Know when to run. Sometimes, it's just not worth it. And if you absolutely HAVE to wipe out the planet for your own survival, swallow your pride and go for the PyrrhicVictory where you wipe out the entire planet and just forget the resources.
# And, if you see a [[Series/DoctorWho blue box]] don't even bother. And if you do bother, and the owner offers a chance to run, for Gallifrey's sake, take it.

See also ''[[ Aliens' Guide to the Conquest of Humanity]]''.