->"He was a candidate for a Midwestern congressional seat, and he hired me to manage his campaign advertising. Unfortunately, his opponent turned up something in his past with which we could not cope."\\
"Let me guess: he was secretly a liberal."\\
"Worse. An alien."\\
"You're kidding?! An undocumented alien running for--"\\
"No. A space alien, Ms. Walters."
-->--''ComicBook/SensationalSheHulk'' #11, Jan. 1990

A character of extraterrestrial origins. For tropes about what ''makes'' them alien, at least from a biological standpoint, see BizarreAlienBiology.

[[Film/{{Aliens}} If you thought it meant "illegal aliens" and signed up]], click RaceTropes. For interspecies romantic or sexual interactions, see the InterracialAndInterspeciesLoveIndex.

If there are no aliens at all, see AbsentAliens.

Compare FantasticSapientSpeciesTropes. Not to be confused with OthernessTropes, though there may be some overlap.
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!! '''Tropes:'''
[[index]]

!!! Levels of the ladder of alien strangeness:
* HumanAliens
** HumanOutsideAlienInside
* HumanSubspecies
** TranshumanAliens
* NotQuiteHuman
* RubberForeheadAliens
** GreenSkinnedSpaceBabe
** SpaceElves
* HumanoidAliens
** TheGreys
** LittleGreenMen
** TheReptilians
** IntelligentGerbil
*** UrsineAliens
*** CatFolk
* AngelicAliens
* FishPeople
* InsectoidAliens
** BeePeople
** InsectQueen
* AlienAnimals
** KillerSpaceMonkey
** SpaceWhale
* MushroomMan
* LittleGreenManInACan
* MechanisticAlienCulture
* BigCreepyCrawlies
* SandWorm
* PlantAliens
* StarfishAliens
** OctopoidAliens
** LivingGasbag
* BlobMonster
* SiliconBasedLife
* MechanicalLifeforms
* LivingShip
* EnergyBeings
* GeniusLoci
* SufficientlyAdvancedAlien
* EldritchAbomination

!!! SFX:
* PeopleInRubberSuits
* {{Muppet}}
* SerkisFolk

!!! Interspecies relations:
* AlienNonInterferenceClause
* AliensAreBastards
* AliensSpeakingEnglish
** AliensOfLondon
* AnatomicallyIgnorantHealing
* AncientAstronauts
* {{Area 51}}
* DescriptivelyNamedSpecies
* FirstContact
* FirstContactFauxPas
* FirstContactMath
* FirstContactTeam
* JustForFun/HowToInvadeAnAlienPlanet
* HumansAreSmelly
* HumansNeedAliens
* HumansThroughAlienEyes
* HumorlessAliens
* IComeInPeace
** TakeMeToYourLeader
** WeComeInPeaceShootToKill
* InnocentAliens
* InscrutableAliens
* KlingonsLoveShakespeare
* MistookTheDominantLifeform
* PlanetLooters
* ProtocolPeril
* PunyEarthlings
* TheRightOfASuperiorSpecies
* RoswellThatEndsWell
* ScaryDogmaticAliens
* ServantRace
* SlaveRace
* StayWithTheAliens
* SuperiorSpecies
* ToServeMan
* WhatMeasureIsAHumanoid
* WhatMeasureIsANonHuman
* TheXenophile

!!! Reproduction:
* BizarreAlienReproduction
* BizarreAlienSexes
* DesignerBabies
* DyingRace
* ExoticEquipment
* FaceFullOfAlienWingWong
* ImmortalProcreationClause
* InterspeciesRomance
** BoldlyComing
** DominantSpeciesGenes
** {{Gendercide}}
** HotSkittyOnWailordAction
** MarsNeedsWomen
** OnlyYouCanRepopulateMyRace
* PlanetaryParasite
* UterineReplicator

!!! Genders:
* BizarreSexualDimorphism
* GenderEqualsBreed
* OneGenderRace

!!! General tropes and other features:
* AbusiveAlienParents
* AlienAbduction
* AlienAmongUs
** HughMann
* AlienArtsAreAppreciated
* AlienAutopsy
* AlienCatnip
* AlienHair
* AlienInvasion
** BenevolentAlienInvasion
** EasilyThwartedAlienInvasion
* AlienKudzu
* AliensAndMonsters
* AliensNeverInventedTheWheel
* AliensStealCable
* AliensStealCattle
* AlternativeNumberSystem
* AmusingAlien
* AnalProbing
* BizarreAlienBiology
* BizarreAlienPsychology
* BlueAndOrangeMorality
* BrainInAJar
* CameFromTheSky
* ChestBurster
* CropCircles
* DittoAliens
* TheDogIsAnAlien
* DramaticAlienVTOL
* EldritchStarship
* ETGaveUsWiFi
* ExposedExtraterrestrials
* FlyingSaucer
* HigherTechSpecies
* ImportedAlienPhlebotinum
* IndoEuropeanAlienLanguage
* InsufficientlyAdvancedAlien
* KlaatuBaradaNikto
* LawOfAlienNames
* MarsNeedsWater
* MarsWantsChocolate
* TheMenInBlack
** JustForFun/IfIAmEverHeadOfAnAlienMonitoringAgency
* MirrorChemistry
* MistakenForAliens
* MoreTeethThanTheOsmondFamily
* MulticulturalAlienPlanet
* MyBrainIsBig
* NamedAfterTheirPlanet
* NoBiochemicalBarriers
* NoSuchThingAsAlienPopCulture
* NotOfThisEarth
* OminousFloatingSpaceship
* {{Panspermia}}
* PeopleJars
* APlanetNamedZok
* PuppeteerParasite
* SolidGoldPoop
* SpiceOfLife
* StarfishLanguage
* StrongerWithAge
* TechnologyUplift
* TheyLookLikeUsNow
* TouchedByVorlons
* TwoOfYourEarthMinutes
* {{Ultraterrestrials}}
* UnusualEars

[[/index]]
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