* AcceptableHobbyTargets: ''The Resistance'' features a family of ''Franchise/StarTrek'' loving campers who are, to put it altogether too mildly, not portrayed in a very positive light. ''Franchise/StarTrek'' fans reading the series later were not amused, though many of the Animorphs, particularly Marco and Tobias, are avowed fans of the franchise.
* AcceptablePoliticalTargets: Surprisingly averted when the world's politicians have their summit meeting in the David trilogy. Played straight with Nazis, who are semi-regularly mentioned by the kids as a shorthand for evil and eventually encountered in ''Megamorphs #03''. The most absurd example is in ''Megamorphs #02'', when Cassie randomly brings up a Nazi-Yeerk comparison that has [[NonSequitur nothing to do with what she was rambling about]]. Though the summit meeting scene manages to slip in a comical shot at a [[NoCelebritiesWereHarmed certain world leader with a comical drinking problem]]. [[spoiler: Probably Boris Yeltsin, for those of you who aren't 90's literate.]]
** At one point in the epilogue, several RightWingMilitiaFanatic groups spring up in response to the discovery of aliens. Not much depth is given to them.
* AlternativeCharacterInterpretation:
** Cassie. Is she TheEmpath who genuinely does not like to emotionally hurt people and persuades others to not hurt others as well, but [[IDidWhatIHadToDo did what she had to]] in a war where the stakes were humanity and Earth? Or is she a sadistic, hypocritical and manipulative bitch that will ''leap'' at the chance to put someone to the psychological thumbscrews if the opportunity arises? Or is she simply a bit of a moron struggling through the war?
** Tobias: Emo with wings, or TheLancer who, as he spends the first books unable to morph, is the only one able to objectively see the risks and benefits of each morph?
** Rachel, valiant and skilled fighter or [[AxeCrazy unhinged psychopath]] (not so much alternate, as her slow drift into BloodKnight and PTSD is canon).
** Marco, TheLancer, tactical and strategic genius, or just an asshole who's only good for coming up with horrifyingly ruthless plans and complaining?
** Jake, skilled leader, or just some insecure jock who made everything up as he went along and led five child solders to their inevitable War-is-Hell mental breakdown?
** David, a lost and confused boy who's had his life completely destroyed and doesn't know if he can trust his "saviors", or a ruthless sociopath who has no qualms about murder and doesn't give a damn about the human race as long as he's safe?
** And Taylor: Cold hearted torture technician or mentally damaged BrokenBird who can only express her bizarre love for Tobias by breaking the bird?
* AngstDissonance: Tobias's backstory counts as this for some.
* AntiClimaxBoss: Visser One/Three at the very end. Anyone expecting a climatic final battle will be severely disappointed when Esplin meekly surrenders to the kids and leaves his host with little fanfare. It's a bit of FridgeBrilliance, though, when one considers the Yeerk mentality mentioned way back in ''#06 The Capture''.
** This was actually specifically addressed by Applegate in her letter to the fans after the series ended, where she responded to criticisms about the finale ending the series on a down note. As she pointed out, such an anticlimactic ending--that is, the battle-hardened soldiers mourning their loved ones and confusedly trying to move on with their lives (and not always succeeding)--is a better illustration of how real wars end than a bombastic, fist-pumping final battle would have been.
* AssPull: Creator/KAApplegate's a good enough writer to usually avoid these, but there's a really glaring one in the David Trilogy. ''The Threat'' ends with the cliffhanger that Tobias has been killed, showing David gloating over a very dead red-tailed hawk. Along comes ''The Solution'' and what happens? Tobias is very much alive, handwaved as just having 'gotten lost' looking for David, and that red-tailed hawk he killed? Just a random red-tailed hawk. Never mind the extreme unlikeliness of a red-tailed hawk following a golden eagle, a species known to be one of its few predators, into the enclosed area of someone's wrecked home, ''in the dead of night''. (red-tails are very much diurnal animals, a fact which is pointed out in Tobias books before this more than once.)
** [[spoiler: In ''The Departure'', we suddenly learn that metamorphosis resets the morphing clock, meaning that as soon as Cassie became a butterfly, she was no longer a nothlit. This was never mentioned before or after that book.]]
* AwesomeEgo: Marco, full throttle.
* AwesomeMusic: The TV show may have been terrible, but many agree the [[https://www.youtube.com/watch?v=0IfboJUVBI8 theme song]] was pretty darn awesome.
* BizarroEpisode: Cassie has a book that's one, ''The Hidden''. A random buffalo somehow acquires morphing powers as the Yeerks cause trouble with Helmacron technology. It's as bad as it sounds.
** Book 41: The Familiar is this as it is really weird and often makes no sense, and at the end is revealed to be [[spoiler: some kind of dream or illusion]] making it unnecessary to the overall plot.
** ''Megamorphs 2: In The Time of The Dinosaurs'': [[ILoveNuclearPower A nuclear sub explodes, tearing a hole in space-time]] that sends all the Animorphs to the time of the dinosaurs. They meet [[AncientAstronauts the Nesk and the Mercora species]], getting caught in the war between the two. For reasons never explained, morphing won't heal Tobias's broken wing in this adventure.[[note]]Applegate later admitted that she wrote "Tobias breaks his wing" in her summary to her ghostwriter after forgetting that morphing can heal injuries. The ghostwriter thus wrote a scene of Tobias trying to heal it but finding it can't.[[/note]] The K-T extinction comet arrives and kills all the dinos and aliens, as well as rocketing the Animorphs back to their own time. After this adventure, [[StatusQuoIsGod the Animorphs find they can not morph into their acquired dinosaur forms]].
** ''The Forgotten'' also counts, for similar reasons. In fact, any book written with the ''Sario Rip'' effect is an instant candidate for a BizarroEpisode.
** For a non-Saario Rip example, there's ''The Prophecy''. A sequel to The Hork-Bajir Chronicles where a recording of Aldrea's personality is put into Cassie. Except the process comes off as pure voodoo that sticks out strongly in this mostly hard sci-fi series, and Aldrea is inexplicably considered to have ''chosen'' to become a Hork-Bajir nothlit rather than being knocked out. Plus, there's a glaring editing mistake that makes the Animorphs look like idiots when they're all shocked and appalled that Aldrea doesn't known where the book's {{MacGuffin}} is, ''after'' she already told them.
** ''The Underground''. Near the end, Jake comes right out and ''[[LampshadeHanging says]]'' that this whole plot is stupid and this battle [[LetUsNeverSpeakOfThisAgain will be forgotten by history.]]
--->'''Jake:''' You know, from the point where Edelman said "maple and ginger oatmeal," I should have known this was going to end stupidly.
--->'''Cassie:''' Instant maple and ginger oatmeal.
--->'''Jake:''' Battles that involve oatmeal are just never going to end up being historic, you know? Gettysburg? No major oatmeal involvement. The Battle of Midway? Neither side used oatmeal. Desert Storm? No oatmeal.
** ''The Mutation'', in which the Animorphs find an {{Expy}} of Atlantis, then escape, and it's never brought up again, with the whole thing being an excuse for an {{Anvilicious}} "war is bad" message. It also doesn't help that the book's ghostwriter was a comedy writer way out of her depth.
* BrokenBase: Some fans liked the secret-guerilla-war aspect of the series, and thought the final story arc ruined the series. Others, conversely, see the final arc as ten shades of epic, and see it as the best-written and greatest part of the series.
** Similarly, some fans liked the, uh, [[NoEnding open-ended]] conclusion, as it brought the series full circle. Some thought it was just an easy (and lazy) way for Applegate to get out of writing a real ending.
** The Helmacrons are either stupid, pointless {{Filler Villain}}s or manage to single-handedly provide some of the series' funniest {{Breather Episode}}s.
* CompleteMonster:
** Esplin 9466 (the greater), better known to the cast as Visser Three. The only Andalite-Controller in existence, Visser Three is the sole Yeerk with the power to [[ShapeShifter morph]]. In his first appearance in the series, he shifts into a horrific monster and [[ImAHumanitarian eats Prince Elfangor alive]], firmly establishing his characterisation for the rest of the series. A low-functioning sociopath with a HairTriggerTemper, Visser Three takes every opportunity he can to kill people, [[OffWithHisHead personally decapitating]] his subordinates and their hosts left, right, and centre. He repeatedly eats those he dislikes, and outrages other Yeerks when he morphs a ''Yeerkbane'', one of their few natural predators, and uses it to devour subordinates who have [[YouHaveFailedMe failed him]]. As the commander of the invasion of Earth, Visser Three cares nothing for casualties, and is willing to [[WeHaveReserves write off thousands of his own Yeerks]], rather then negotiate. He is the [[BadBoss worst boss]] in the series, and no matter how awful things got, always gave the Animorphs the most nightmares.
** Crayak, is a SufficientlyAdvancedAlien who acts as the series' {{satan}} equivalent. A nearly omnipotent [[TheSocialDarwinist Social Darwinist]], Crayak seeks to create a universe ruled by one species and one species alone. To that end, Crayak engineered the Howlers, a race of psychopathic {{child soldier}}s who think that killing is a game, and used them to gruesomely exterminate countless species, including the [[PerfectPacifistPeople pacifistic]] Pemalites and Graffen's Children. In order to ensure that the Howler's HiveMind is never contaminated by memories of defeat, Crayak obliterates any Howler's who [[YouHaveFailedMe fail him]]; he also destroys any Howlers who realise that their victims are people too. Not content with having created one of the most feared races in the galaxy, Crayak also lends his godlike might to other vicious species, secretly backing the Yeerks and other would-be {{galactic conqueror}}s; he plans, for example, to have the Yeerks enslave humanity, only to then be wiped out by the Howlers. In a series filled with shades of grey, Crayak was as close to pure, unadulterated evil, as one was likely to get.
** While she might not have operated on the same scale as [[BigBad Visser Three]] or [[PhysicalGod Crayak]], there were few antagonists in the series who could match [[SociopathicSoldier Subvisser Fifty-one]]--better known by her host's name of "Taylor"--when it came to sheer visceral cruelty. A case study in why one does ''not'' allow an already AxeCrazy [[PuppeteerParasite Yeerk]] to infest a [[TheMentallyIll mentally ill]] girl, "Taylor" combines her host's anger with her own Yeerk ruthlessness to deadly effect, acting as Visser Three's TortureTechnician. Capturing [[TheWoobie Tobias]] she subjects him to brutal [[ColdBloodedTorture torture]], using a device that tampers with the pain/pleasure centres of the brain, forcing him to relive the worst moments of his life, or inserting agony into even the fondest memories. When his friends try to rescue him, she runs off with him and starts torturing him physically even as she makes her escape, stopping only when Rachel finally frees him. Returning months later, the demoted subvisser reveals she has severed her mental link with her host, regaining much of her sanity, but none of her morality. Manipulating the Animorphs into helping her with a plot to kill Visser Three, "Taylor" relentlessly taunts Tobias about her treatment of him, trying to provoke him into a fight so that she'll have an excuse to hurt him some more. She then reveals that her actual plan is to blow a gas main near the Yeerk Pool, killing thousands of her fellow Yeerks; she will then pin the blame on the Yeerk Peace Faction. An insecure [[TheBully bully]] possessed of a raging [[InferioritySuperiorityComplex inferiority complex]], "Taylor" is the postergirl for everything wrong with the Yeerk military, and shows just how banal even the sickest individual can be.
* CreatorsPet: Arguably Cassie. She's the stated favorite of writer K.A, she is the only character in-series to win the SuperpowerLottery (being both an estreen ''and'' a temporal anomaly) and she is usually praised and defended by the narrative even when it's completely unwarranted - take for example ''Megamorphs #02'', when Marco privately compliments Cassie for going on a whiny rant about killing a Triceratops, or ''#53 The Answer'', when Tobias harshly criticizes Jake for excluding Cassie from the war council despite the fact that he had extremely good reason to (that reason being that she betrayed the whole team by allowing the blue box to be seized by the Yeerks, and all for a 'gut feeling' that [[GambitRoulette she's lucky to see pan out]]). She criticizes the others from start to finish, puts the whole team at risk on multiple occasions, and is the only character to [[IncorruptiblePurePureness never learn or grow in any way]]. [[spoiler:This even extends to the epilogue, where she is the only Animorph spared by the BolivianArmyEnding.]]
* CreepyAwesome: Despite appearing in only one book, Joe Bob Fenestre stands out as one of the series' most intriguing antagonists. Possibly because he's the Animorphs equivalent of [[TheSilenceOfTheLambs Hannibal Lecter]].
* DarknessInducedAudienceApathy: Animorphs was never a particularly lighthearted series but by the end it's comparable to Game of Thrones. The main characters are traumatized anti-heroes at best and psychopaths at worst, (see AlternativeCharacterInterpretation) both sides in the Yeerk vs. Andalite war have been shown to have committed atrocities to the point where it's hard to say that anyone is morally superior, most of the humans are horribly outmatched and have virtually no say in their fate, when the Animorphs finally call the Andalite homeworld the aliens' response is to "Quarantine" planet Earth, thereby mark it for destruction, and to top it off two god-like characters, one named Crayak and the other named the Elimist, are locked in a "game" that will result in the universe being destroyed.
* EnsembleDarkhorse: Tobias and Ax both qualify. They were given only one book per ten-book cycle because Scholastic didn't think they'd be as popular as the four main kids. Boy were they wrong about that...
* EscapistCharacter: Tobias counts as this for a lot of first-time readers. What kid doesn't want to just fly away from their problems?
* EvilIsSexy: Subverted. Taylor is described as very attractive, but is so artificial and emotionally screwed up that no one cares. Pointed out by Tobias when he morphs Taylor and recieves far more positive male attention than the real thing:
--> "We were mirror images, literal carbon copies. But I was alive. Taylor wasn't. Not really. I had a sense of humour. Taylor had a coldness that enclosed her like a shield. The kid could see this. Anybody could."
** The first Visser One may also qualify.
* FamilyUnfriendlyAesop: The book where they turn into cows. Sure, animals are treated horribly in meatpacking plants, but [[CarnivoreConfusion burgers are delicious]]!
* FanNickname: Emohawk for Tobias. Visser Mom for Estrid/Eva.
* FanonDiscontinuity: A lot of fans simply gloss over some of the more awful ghostwritten books.
** The ending of the series, partly for the lack of a proper conclusion, partly for a BolivianArmyEnding and partly for being full of absolute NightmareFuel.
* FoeYay: Largely averted between Taylor and Tobias. It is ''possible'' to read her obsession with capturing and breaking Tobias (and some of the [[WeCanRuleTogether lines she says to him]]) as rather FoeYay-y, but it requires you to ignore her personality. She's described as so cold, nasty, and downright insane that most of it comes off exactly the way it's supposed to: as the behaviour of an insecure, sadistic bullying bitch who doesn't like letting her victims get away. {{Yandere}} she ain't.
** Arguably, David and Rachel -- he also gets in a WeCanRuleTogether line in book 22 (his specific words are "we could hook up," though that might just be '90s slang), and there are hints that the team (well, mostly Cassie) picked up on the dynamic between them and used it to trap him.
* GameBreaker: Cassie, in-universe. Her natural ability as a 'temporal anomaly' allows her to see through the [[RealityWarper reality warping]] powers of beings like the Drode, and her presence in any timeline that's not the 'real' one will ensure the fake timeline breaks down. [[LampshadeHanging Lampshaded]] by the Drode himself, who angrily accuses the Ellimist of '[[FixingTheGame stacking the deck]]' by including her on the team.
* HarsherInHindsight:
** In the alternate future Jake visits in #41, the only part of the New York skyline still recognizable is the World Trade Center.
** In book #37, Rachel deliberately crashes an airplane into a skyscraper.
** Also, in book #46, there is discussion of how America is complacent because they have no real enemies. And then Ax threatens to fly a plane over the middle of a town and detonate a nuclear device.
** In book #54, which was published in May 2001 but set [[TwentyMinutesIntoTheFuture in 2002 or thereabouts]], Jake mentions that since the existence of aliens was revealed to the general public there's been a rise in terrorism, particularly religiously motivated terrorism.
** In Megamorphs #2, the Animorphs help rescue a nuclear submarine that has gone down. After they finish, Ax asks what the submarine is for, since he figures its too large to be an exploration vessel. Jake explains that its part of the navy, which leads to this conversation:
-->
--> [Jake] said, feeling fairly idiotic.
--> Marco said brightly.
** The final arc, which featured a WarIsHell {{Aesop}} was gut-wrenching, incredibly sad... and came no more than four months before the U.S. entered an actual war.
* HilariousInHindsight: More than a decade after the series ended, Applegate wrote another book featuring talking animals, specifically a gorilla and an elephant. Granted, they had no similarities to Marco and Rachel whatsoever, and since it was based of real events, they had to be those animals, but it's still pretty funny.
** Crayak was doing [[MemeticMutation "Soon"]] before it was cool.
* IdiotPlot: The series has a few.
** ''The Conspiracy'' has been criticized for being an idiot plot, both on the part of the yeerks and the Animorphs.
** ''The Answer'' has had similar criticisms.
** The recurring plot with the Yeerk Peace Movement can also be taken as an idiot plot, in that the Yeerks could always infest animals that weren't sentient, as proved in ''The Unknown''.
** Also, ''The Hork-Bajir'' chronicles has a small element of this, because the Arn never think to create quickly-reproducing bodies for the Yeerks to infest.
* ItGetsBetter: The beginning of each book is loaded with the same exposition about the Yeerks and "I can't tell you my last name" and "We can't stay in a morph for more than 2 hours" and "You see, every three days they have to..." and so on.
* JerkassWoobie:
** David - lost his entire life through no fault of his own, was kidnapped by kids he didn't know and forcibly recruited into a war he wanted no part of and faced the threat of death from both sides of the conflict. His [[FateWorseThanDeath final fate]] just hammers the nail in.
** Taylor - lost her arm, leg, and face in a fire. Became a human-Controller in exchange for getting them back. Got infested by a psychotic Yeerk, whose fusion with her own unbalanced mind drove them ''both'' over the edge. She'd be pitiable if she weren't so evil (this applies to Taylor the Girl, and not her Yeerk Subvisser Fifty-one).
* MarySue: Deconstructed with Estrid. Gets hit on by a main cast member, genius, expert tail fighter, estreen, got into a university despite sexist Andalite beliefs...[[spoiler: And all it did was get her recruited into a secret project to eliminate the Yeerks via biological warfare, a mission it's implied that they would have executed her for by the end of it to keep it covered up and avoid controversy.]]
* MagnificentBastard: Visser Three and Visser One approach this in their respective backstories, before the VillainDecay(and in Visser Three's case, insanity) set in. David and Tom both fancy themselves to be this, but are usually seen as just {{Smug Snake}}s. The one who probably comes the closest to this trope is, of all people ''[[TheHero Jake]]'' who really cracks out the gambits before diving into WhatTheHellHero territory.
** [[BigGood The Ellimist]]. ''Megamorphs #04: Back to Before'' cements it.
--> '''Drode:''' Oh, I see it now, I see it now. Subtle as always, Ellimist. Your meddling came ''before'', didn't it? How could we not have seen it? [[TheDutifulSon Elfangor's brother]]? His [[TheChosenOne time-shifted son]]? This [[GameBreaker anomalous girl]] here? And the son of Visser One's host body? A group of six supposedly random humans that contains those four! You stacked the deck!
--> '''The Ellimist''' (laughing) Did I? [[MagnificentBastard That would have been very clever of me]].
* MemeticMutation: There seems to be a growing number of spoof Animorph covers involving strange transformations. Sometimes [[http://24.media.tumblr.com/tumblr_m759l0Z8DS1r7kc6xo1_250.jpg not even between a human and an animal]].
** There's a rather [[InternetBackdraft infamous]] spoof cover of Cassie morphing into a watermelon [[UnfortunateImplications Yeah]].
** And then there are those with celebrities with animal names morphing into their respective animals, e.g. Pitbull, Seal, Snoop Dogg (after he renamed himself Snoop Lion)... and even [[Series/SexAndTheCity Sarah Jessica Parker]] morphing into a horse (because according to MemeticMutation she looks like one).
* MoralEventHorizon: [[spoiler:David]]'s murder/replacement of Jake and Rachel's cousin Saddler is played this way. Previously given some sympathy due to his having lost his parents and been forcibly recruited by the Animorphs into a war he doesn't want to fight, [[spoiler:David]]'s attacks on Tobias and Jake were the start of a slide down the slope to straight up villainy, but were not unforgiveable. [[spoiler:David]]'s decision to unplug Saddler, stash the body, and replace him, is the point at which the characteres and the narrative stop treating him with any sympathy, and the point at which the audience realises that there is going to be no reconciliation.
** Some members of the fanbase--and Jake himself for that matter--view his [[spoiler:execution of 17000 defenceless Yeerks]] as one of these. While Jake clearly feels bad about it, it's an action from which there is indeed, no going back.
* {{Narm}}: Rachel threatening David with a plastic fork in the ear. It's both intensely disturbing and somehow hilarious in its simple and straightforward language.
-->"He stepped back, drew back his fist, and swung on me. I dodged the blow. I grabbed his head with one arm and jammed the fork against his ear. I fought a nauseating urge to [[EarAche twist the fork, to make him scream in pain]]."
* OnlyTheCreatorDoesItRight: Frequently invoked by the fans in response to the ghostwritten books. Scholastic ''themselves'' invoked it once, when K.A. had to do a last-minute rewrite of ''#28: The Experiment''. Amusingly, the much-maligned ''[[JekyllAndHyde #32 The Separation]]'' is frequently cited as an example, [[MisBlamed when in fact that book was written by K.A. herself.]]
* PairTheSpares: Possibly. One episode of the tv adaptation ends with [[spoiler: all six protagonists slow-dancing to a romantic song: Cassie and Jake, Rachel and Tobias, and Marco and Ax. In the US, this was the last episode aired, and it's pretty easy to interpret it as a LastMinuteHookup.]]
* ParanoiaFuel: Thanks to their fantastic capacity for imitating their hosts, Yeerks can be anywhere, even inside the people you know intimately. Yes, you could be talking to an alien parasite who's putting on an elaborate act and doesn't mean a word he/she says while your genuine best friend/close sibling/beloved parent/ significant other is watching you be fooled, and is mentally sobbing because no one realizes they're a prisoner inside their own head, and you'd have no way of knowing. ''At all.'' The yeerks make a few rare mistakes, due to having their own agendas and personalities, but aside from a couple isolated incidents the yeerks are absolutely undectectable. Combined with the books' LiteraryAgentHypothesis setup, this makes for some very creepy MindScrew.
** Also because ot the LiteraryAgentHypothesis, you realize that the insect you just killed could have been one of the Animorphs.
** Even though the Chee are good guys, the concept of people around you being NighInvulnerable extraterrestrial robots using holograms to make themselves look human is rather unsettling.
* RescuedFromTheScrappyHeap: Not hated persay, but in it's heyday, Jake was the most criticized character of the group [[StandardizedLeader for lacking the depth]] that others like Marco, Tobias, and Rachel had. CharacterDevelopment kicked into high gear during the [[CerebusSyndrome second-half of the series.]] and these complaints disappeared.
* RetroactiveRecognition: Shawn Ashmore as Jake would go onto do Xmen and Paulo Castanzo as Ax would later go onto to {{Series/Joey}} and later RoyalPains.
* TheScrappy: [[GiantSpaceFleaFromNowhere The One]] is widely loathed for bringing about the BolivianArmyEnding.
* ScrappyMechanic: The ''Sario Rip'' effect. It's a thinly-veiled way to send the kids on fantastical journeys to places like the Amazon or the Cretaceous, and it comes with a built-in reset effect that [[StatusQuoIsGod makes anything that happens during it irrelevant]]. The kids get all kinds of cool morphs they don't get to keep because of it, and the books where it is featured are usually a lot less fun than they were meant to be.
* TheyWastedAPerfectlyGoodCharacter: An unfortunately inevitable outcome of combining ghostwriters with a series featurings LoadsAndLoadsOfCharacters. Some of the best villains the series produced, like Joe Bob Fenestre in ''The Warning'' and Arbat-Elivat-Estoni from ''The Arrival'', were one-shot characters that were never seen again. Other characters, like Aftran 942 and David, returned irregularly but are lamented among fandom for never being utilized in the way they deserved to be.
** The multiple RightWingMilitiaFanatic groups are mentioned in the epilogue... and that's it.
* TrappedByMountainLions: ''Rachel'', of all people, is subjected to this in the first Megamorphs book, ''The Andalite's Gift''. The first half of the book has her contracting an unfortunate case of EasyAmnesia and wandering around the woods while her friends are fighting for their lives.
** Taking the series as a whole into account, entire books can count as this. ''The Mutation'', ''The Hidden'' and ''The Journey'' are great examples of entire books featuring the Animorphs getting caught up in bizarre and irrelevant sideplots that have no consequence to the main conflict of the Yeerk invasion.
* {{Wangst}}: [[FanNickname "Emohawk!"]]
** Also, David, who never stops whining about how unfair it is that he's "lost everything" even as he tries to murder the kids.
* WhatDoYouMeanItsForKids: In ''VISSER'', there are several implicit references to drugs. Jenny Lines is heavily implied to be a drug addict when Edriss said in the narration, "The only thing she really cared about was [[GRatedDrug a certain human substance]]." They couldn't actually say what the substance was
** This also apples to Hildy in the same book; he was heavily implied to be an alcoholic. To get him to talk, Visser Three said he'd give him a "bottle", but Applegate couldn't exactly say what was in the bottle.
** This has spawned the popular fandom joke that K.A. told Scholastic [[GettingCrapPastTheRadar it was a bottle of milk]].
** In recent years, the books have had a relatively large following with adults who read the series as kids. Some adults are just now discovering it, without knowing that it was intended for children. It's not hard to see why - it's ''incredibly'' dark and violent, and there are some concepts (such as drug abuse) subtly (or not-so-subtly) presented in the text that a kid simply wouldn't get.
* TheWoobie:
** Tobias. He starts the series out as a skinny, blond-haired loser Jake saves from bullies... and Jake is the closest thing he has to a friend, despite the fact Jake thinks he's weird. His parents are dead, his only two relatives fight over which one of them HAS to have him. He then gets trapped as a hawk by the end of the first book. He then goes on to have an epic identity crisis, start a semi-InterspeciesRomance with a girl who really wants him to drop the "interspecies" bit, realize that [[spoiler:the alien who died saving them is his father]], get captured and tortured, realize that his mother isn't dead -- she's ''[[spoiler:amnesiac and crippled]]'', and [[spoiler:watch Jake send the love of his life to certain death]]. About the only good things that happen to him are Rachel, his girlfriend, and Ax, his best friend and [[spoiler:[[LukeIAmYourFather uncle]]]]. [[spoiler:They both die.]] For a series as dark as this one, Tobias stands out for his Woobieness.
** The worst part is that he honestly feels his new situation is an improvement. Stuck fighting an alien invasion involving thousands of conspirators with only four human kids while trapped in the body of a hawk and fighting the instincts of the hawk to retain his own humanity is a step UP for him.
** Really, every character falls into some category on the Woobie spectrum. Even David has his moments. About the only one who can't be considered Woobie-ish to some extent or another is Visser Three himself.
*** Even then, you have to feel sorry for Alloran-Semitur-Corrass, Visser 3's host body: A highly respected warrior who [[MyGodWhatHaveIDone unleashed a horrible biological weapon on an allied world]] [[IDidWhatIHadToDo to try and prevent the Hork-Bajir from being enslaved.]] After that, he was saddled with two recruits, one of whom (Elfangor) is directly responsible for him being captured and infested, becoming the first -and only- Andalite Controller in the entire war. He spent the next 20 or so years [[AndIMustScream watching as his body was used to murder countless innocent people]], gaining him the title "The Abomination" by the rest of his species. Before being taken, he had a wife (Jahar) and two children.
** Tobias is more of an IronWoobie, really.
* WoobieSpecies: Many aliens.
** The Yeerks are the misunderstood variety [[JerkassWoobie for the most part]]. They are blind, sentient slugs who only take hosts to compensate for their biology. Only those in power and those seeking power can be said to be really evil, as most of the footsoldiers are either swept up in the propaganda or afraid to challenge their superiors.
** The Taxxons suffer from terrible HorrorHunger. They're a race of terrified over eaters, cannibalising one another out of a terror of starvation.
** The Hork-Bajir were race of dumb, friendly bark eaters who were nearly wiped out in an attempt to deprive the Yeerks of hosts.
----