- Fire Lord Ozai. The fact that he's voiced by Mark Hamill (also known as the Joker) and never shows his face during the first two seasons doesn't help at all.
- Ozai's daughter, Princess Azula. A sociopathic fourteen-year-old girl who is not only a Child Prodigy and one of the most powerful and skilled firebenders in the world, but also a Machiavellian-style tactical genius and a metaphorical and literal Hero Killer.
- The Fire Nation proves to be one to not only the audience but the entire Avatar world as well. They're basically fire-slinging Nazis that go around assimilating territory and annihilating whatever gets in their way. Under the rule of Ozai's father and grandfather, the Fire Nation annihilated the entire race of pacifistic Air Nomads and went on ritual pogroms towards Water Benders as well. The Nation's forces even attempted to scorch the entire Earth Kingdom and its people to ash near the end of the series. The blatant jingoism of its people portrays how dangerous patriotic zealotry and fanaticism can be for a nation.
- The Avatar State. Aang loses control and turns from a kind, Cheerful Child into a cold, merciless Creepy Child with the Voice of the Legion and Glowing Eyes of Doom."TELL ME WHERE APPA IS!"
The Southern Air Temple
- The episode the first jaw-dropping instance of nightmarish imagery the show spit out- the moment Aang spies a heap of Fire Nation soldiers' skeletons all gathered around another skeleton leaned against the wall- Monk Gyatso's. Not only are they the first legitimately depicted deaths in the series, but it's on a scale of its own when you realize it premiered on Nickelodeon- a kid's show network. Then you see that they're all charred black... meaning they burned to death; killing people by burning them alive... on a children's show! Worse, Aang goes into a terrifying rage that sets off his Avatar State and he loses control. Everything around him turns dark, he surrounds himself in a sphere of wildly spinning air powerful enough to kick up a tornado, and starts levitating. You can only see his shadow-obscured face with cold, glowing eyes and an eerie whirring sound pulsating from him.
- Place yourself in Aang's shoes: scared of his responsibility as the Avatar, he leaves his friends and possibly his family, and to him that was only a few DAYS ago. Then he sees the skeletal remains of his people and teachers after holding some desperate hope his people were still alive. That's when reality sets in and he realizes the horrible truth: he's completely alone and truly the last of his people. Who knows what Aang would have done had Katara not stepped in to comfort him.
Winter Solstice, Part 1: The Spirit World
- The Hei Bai Spirit is as freakish in its appearance as its behavior. Although it appears as a panda bear when docile, when pissed it becomes an unstoppable six-legged, light spewing, black-and-white monster that destroys everything in its path and moves in flashes. Not to mention it had a disturbing habit of terrorizing a village near its protectorate forest by abducting one villager each day despite the Fire Nation being responsible for the destruction of its forest. Eventually it might have taken them all and it managed to take Sokka!
Winter Solstice, Part 2: Avatar Roku
- We see Fire Lord Ozai for the first time albeit only a vision of him. The terrifying part? He's seen completely in shadows surrounded by flames before he roars a huge stream of fire and generally looks demonic. It's here where both we (and Aang) realize what he truly has to defeat.
- The titular character, who plans to flood a valley, killing an entire town's worth of Fire Nation soldiers and civilians alike. Keep in mind that he can't be older than sixteen, yet he's trying to commit mass murder on a whole town of innocent people just to get rid of the Fire Nation troops.Jet: Now listen, you are not to blow the dam until I give the signal. If the reservoir isn't full, the Fire Nation troops could survive.The Duke: But what about the people in the town? Won't they get wiped out too?Jet: Look Duke. That's the price of ridding this area of the Fire Nation.
- Jet's insane fervor against the Fire Nation would not be the first instance that the series would present and speaks volumes of how awful the Fire Nation has been since Aang has been on ice, as well as the disturbing He Who Fights Monsters issue of many who are fighting the Fire Nation.
- The episode is a double whammy:
- There's a very poignant Adult Fear moment from Gyatso when he realizes that Aang's just run away... and there's a massive storm brewing outside. Not to mention he never sees the kid again and soon after is killed as part of the Air Nomad genocide when the Fire Nation invades.
- More famously, there's that scene where we see the Fire Lord Ozai (or rather, hear him) torching his son Zuko's face. Zuko is 13 years old, crying, and begging for mercy - and screaming. Oh God, his SCREAM. The poor kid is terrified, and you can practically hear how betrayed he feels. Worse is Zhao's look of content when he witnesses the outcome of the Agni Kai firsthand. Iroh, on the other hand, can't bear to watch and turns away. But the scariest reaction is the one that comes from the girl next to him, who smirks with delight and clenches her fist as though Zuko was finally getting what he deserved and being knocked down a peg or two after mommy kept showing him more attention and favoritism. Come season finale time, we learn that girl's identity: Azula. And then it hits you: Azula was overjoyed watching her own, kind-hearted brother get his face seared to a crisp. That's the first warning sign of how twisted, deranged, and utterly inhumane she's become upstairs.
The Blue Spirit
- The Yu Yan. These guys are the best archers in the entire Fire Nation, possibly the entire world, and when ordered to have absolutely no qualms about ganging up on a twelve-year-old boy like a pack of wolves. Just the look on Aang's face after they have him pinned to the log.
- Even before it's revealed to be Zuko, the Blue Spirit persona is incredibly creepy due to its silent Implacable Man accuracy, stealth, and lethal precision with dual blades. It's no wonder Aang screamed in genuine terror when he showed up swinging his swords.
The Waterbending Master
- We get some good Adult Fear when Iroh goes out for a walk, leaving Zuko alone on the ship... When a group of pirates come to blow it up. We cut away from the explosion—to Iroh's reaction to it. Imagine leaving the boy who is like your son alone for ten minutes, and coming back to find the place where he was ablaze, with no sign of life anywhere.
- Add to that the knowledge that Iroh already knew the pain of losing a son, and you have a Tear Jerker moment as well.
The Siege of the North, Part 2
- The scene with Koh the Face Stealer. Koh is an Eldritch Abomination with a centipede body and many faces he can wear like masks. He switches between faces by "blinking" an eyelid-like flap over his face. His voice is straight out of the Uncanny Valley, like a cross between Jigsaw and Tom Waits. And when you meet him, you must maintain a perfect poker face. If you show any emotion in your expression at all, he'll add your face to his collection and leave you as a blank."You've come to me... with a new face."
- The whole atmosphere around Koh's cave is carefully calculated to build tension, rising to a peak when Aang sees a monkey outside the cave... a monkey with no face.
- A little bit later, Koh shifts into the face of a screeching mandrill—this may have been that monkey's face.
- It's not helped at all by the fact that Koh says something like it's been a while since he's gotten a child's face. That's right, Koh was excited about taking faces from children.
- At one point when Koh's back is turned, Aang has a Eureka Moment and lets out an excited "That's it!" to which Koh responds by immediately swooping in to try and snatch Aang's face off. Fortunately, Aang goes back to his Poker Face just in time, but it's still a pretty chilling moment.
- The whole atmosphere around Koh's cave is carefully calculated to build tension, rising to a peak when Aang sees a monkey outside the cave... a monkey with no face.
- The result of Zhao messing with the Moon Spirits is pretty unnerving. Putting one of the spirits in the bag was enough to turn the Moon, sky, and everything else Blood Red as well as take away waterbending. Killing it made the Moon disappear from the sky!
- Aang and La fusing together to become the Koizilla monster after Tui is killed by Zhao. The moment when you realize it's not Aang in there, but a vengeful and angry ocean god possessing him and proceeding to single-handedly annihilate the invading forces. The music is also quite ominous and intense in this scene.
The Avatar State
- An Earth Kingdom general attempts to get Aang to use the Avatar State at will. He tries to provoke Aang into entering the Avatar State by actually Earthbending Katara INTO THE GROUND as if she's in quicksand, and she disappears while screaming in pain and fright. Needless to say, this provoked Aang to go into the Avatar State, and he goes berserk and starts attacking everybody in a blind rage.
- The atmosphere of the episode was incredibly creepy.
- Early in the episode, the Gaang hears a bird with a cry that sounds exactly like a human scream, disturbing all of them, because they can't find where the sound is coming from.
- The visions. Katara thinks she sees her mother, only for it to be an illusion. She collapses to the ground in tears. Then, Sokka sees Yue, who says in a creepy, echoing voice: "You didn't protect me." She disappears... and when Sokka turns around again, she's right behind him, staring at him blankly, accompanied by a scare chord.
- Vision!Toph's laugh is downright creepy due to it having a echoic effect.
- The swamp actually has a mind of its own.
- Huu's swamp-monster disguise made out of vines. The way it glides around is unnerving, too.
- The swamp is terrifying. Two words: Tentacle. Vines. They slither up to you whilst you sleep and then DRAG YOU OFF, SCREAMING.
- The spider that built a web in Sokka's mouth at the beginning? *bwuaaaah* Doubles as Nausea Fuel.
- The whole notion that the people of Chin Village wanted to kill Aang, a child, for an act one of his past lives committed is unsettling. Even worse when it's revealed that Kyoshi, the past life in question, wasn't even guilty and they still wanted to kill Aang using one of many punishments displayed on a raffle wheel. The punishments included being put on a bed of nails, being put on a whipping post, boiled in oil, eaten by shark, thrown in a razor pit, mauled by platypus bear, and burned alive.
- Zuko's memories are absolutely TERRIFYING in their depiction of Azula as a true fledgling sociopath. Zuko mentions that she "feeds" the sweet little turtleducks by throwing fairly large rocks directly at the ducklings, and while her other acts of petulance and spite are childish, they are a definite foreshadow of what she'll be like later. The fact that she can completely switch personalities and play the innocent so convincingly even when her mother knows how manipulative she can be is quite chilling, as is her total lack of empathy for her "friends" and her family, even after their mum is banished, her only reaction is to taunt Zuko with how she's no longer there to stop her tormenting him. However, the bit where she opens Zuko's bedroom door at night and happily sings "Dad's going to kill you!" and explains every detail of why she's certain and, for once, isn't lying is one of the scariest moments of Creepy Child Troubling Unchildlike Behavior in history.
- Never make Wan Shi Tong angry. EVER. His punishments include killing and stuffing intruders to put on his display wall.
- The part where his neck stretches out and he starts screeching is terrifying and shows he's less a spirit and more of a pissed off Animalistic Abomination.
- Aang in the whole episode. Sure, Katara calms him down before any real damage is done, but think about it...this one sandbender stole a rare animal. It turns out it belongs to the Avatar, who is very, very upset about losing his one living remnant of his people. And then Toph says one thing too many, and Aang's eyes start glowing. At this point, there is nothing the sandbenders can do to get him back. They start pleading, saying they'll help in any way they can, but they quickly realize that he's beyond reasoning. Eventually, Sokka just grabs Toph and makes a run for it along with them.
- Preceding that, Aang saving Momo from the Buzzard Wasp. While it is meant to overlap with awesome for the rescue, Aang blasts the wasp and it drops straight to the ground. Aang, raised his entire life as a Martial Pacifist and respect for life, is so distraught and angry at another loss after Appa that he, without hesitation or even a lingering thought, by all appearances killed a creature in one blow.
City of Walls and Secrets
- It may be a "kid's show", but there is no way in hell that the bit where Long Feng introduces the replacement Joo Dee wasn't designed to terrify everyone watching.
- The swamp is scary. Bloodbenders are terrifying. Joo Dee being replaced? Easily the most horrifying moment in the entire series.
- The music that first plays when Joo Dee is introduced. Just THAT should show you that she's bad news...
- Even before you know about the brainwashing, that constant, creepy, fake grin the Joo Dees have is very... unsettling.
- The entire episode counts as one. The mysterious secrets...The tortuous brainwashing...The Perpetual Smilers...The denial about obvious facts...Really, the episode seems to be a love letter to George Orwell's 1984!. Ba Sing Se might as well be called Oceania in any case.
- The Dai Li themselves are insanely terrifying to have as enemies. They're some of the city's and by extension the Earth Nation's strongest Earthbenders that rely on stealth and precision and can swarm their targets by clinging to walls like spiders with sheer numbers and deadly silence. They're responsible for stamping out any dissent within the city and are greatly feared by every social caste because of how successful they are at their jobs. It only took a handful to take down the Earth Kingdom's generals and stage a successful coup with Long Feng in charge. As Azula aptly put, whoever controls the Dai Li controls Ba Sing Se.
- Jet's brainwashing at the hands of the Dai Li. He even gets brainwashed with a trigger phrase to make him a loyal pawn of Long Feng if needed.
- The situation for the Earth Kingdom becomes quite nightmarish when examined closely. The Earth Kingdom is literally the last and only effective force that can do battle with the imperialistic and destructive Fire Nation led by the psychopathic Fire Lord Ozai and the kingdom is literally spread out in individual towns slowly being dominated by the Fire Nation and citizens abused by Fire Nation troops and Earth Kingdom soldiers alike as seen in Zuko's travels. The Kingdom's last stronghold of Ba Sing Se, the place all desperate refugees are trying to flee to after hearing false tales of sanctuary and good living, is actually a highly segregated caste system society where the poor refugees are shunted off into crowded slums left to starve and everyone else is constantly watched by the Dai Li Secret Police while the Earth King is none the wiser. Think a fantasy form of North Korea but worse. On top of that, the whole kingdom is being fed knowledge that the war between the Fire Nation and Earth Kingdom is not happening by the Dai Li and their leader Long Feng trying to turn the kingdom into his personal puppet state. As a whole, the situation is an absolute nightmare for any Earth Kingdom citizen trying to find sanctuary.
Appa's Lost Days
- The scene of the circus. That episode won an Annie award for its REALISTIC portrayal of animal abuse in the circus. Sweet dreams...
- It's also a rare subversion of the Bloodless Carnage- if you watch Appa try to yank out the quills in his body stuck in him from his scuffle with the boar-q-pine, he bleeds out.
- The scene where the Gaang see a room full of women being brainwashed into being "Joo Dee". Made even worse by the fact that after being creeped out by it when they see it the Gaang never brings it up again. Even when trying to bring down Long Feng, Logai is only brought up as proof on Long Feng trying to control the King, and Jet's brainwashing is mentioned once. But the Hundreds of Joo Dee's? Never come up.
Crossroads of Destiny
- Aang goes into the Avatar State and rises into the air, encased in a pillar of light. Katara looks on with admiration and awe, the music gets upbeat and seriously epic, and it looks like we're about to see a repeat of the Book One finale... and then Azula fries him with a bolt of lightning, in the middle of the transformation sequence. Worse, Aang is left with a gaping scar dead center in his back where the lightning hits, big enough to burn off a good deal of his arrow tattoo, plus a second one where the lightning came out the sole of his left foot.
- Azula in the final two episodes of Book Two as a whole is very unnerving to watch. We've already seen how much more dangerous she is than Zhao was, and even before the outcome of all of her plans is revealed, the sheer composure and confidence with which she carries herself as she puts those plans into motion gives the two episodes a far more sinister and foreboding atmosphere than the Book One finale did even at its most dire moments.
- The fact the Fire Nation have taken over the world at the point of the story after the Earth Kingdom fell once Azula took over Ba Sing Se with the only remaining forces left free being the Water Tribes who stand no chance against the Nation. On top of that, the whole world thinks the Avatar died at Ba Sing Se, destroying most people's hope that the Fire Nation can be stopped.
- Combustion Man. The Voiceless, hulking mercenary bent solely on murdering the Avatar. We don't know anything about him aside from the fact that he can make things explode with his mind.
- The episode is supposed to be a Breather Episode for the bad guys. Supposed to be. But it still has character development moments for Team Azula (and Zuko).Prince Zuko: I guess you wouldn't understand, would you, Azula? Because you're just *so* perfect.Azula: Well, yes, I guess you're right. I don't have sob stories like all of you. I could sit here and complain how our mom liked Zuko more than me, but I don't really care. (somewhat sadly) My own mother... thought I was a monster... (matter-of-factly) She was right, of course, but it still hurt.
The Avatar and the Fire Lord
- The dragon catacombs. Dragon skulls strewn about make for some awful childhood nightmares.
- Let's not forget how Avatar Roku actually died: poisoned so badly by volcanic gas paralysis sets in, his vision turns dull and blurry, and he can't breathe at all. Then Sozin, his best friend for life, pulls the mother-of-all backstabs in the series and leaves him to be buried under the unbelievable heat and airless horror of an avalanche of volcanic ash. Fang, Roku's own dragon, can't rescue him in time, causing him to make a futile effort to shield him from being buried alive, but that only serves to kill them both. At least Roku isn't too upset about showing his own demise to Aang, but Ta Mihn had to have been destroyed by his loss.
- Bloodbending—the art of turning someone into a People Puppet by Waterbending his or her body fluids.
I've never felt more alive.
- When Katara discovers she bent Hama's blood. She breaks down crying after this. Not to mention the reason why she had to bend Hama's blood: Hama was about to force Sokka and Aang to kill each other, which is some prime horror on its own.
- It's also very disturbing to see Hama's veins engorge right before she bloodbends.
- And they were so kind as to take it Up to Eleven in The Legend of Korra. It makes perfect sense why Katara would outlaw the practice.
- Hama herself. She seems like a kindly old woman at first, but by the time you reach her final moonlight duel with Katara, the animation and lighting make her incredibly disturbing. Wrinkled, twisted features, veins popping out her arms, long willowy hair and skeletal hands with nails like claws. The scariest feature has to be the Slasher Smile.
- Hama kidnapped people and kept them underground! She is a blood bender! And she has a very powerful motive for revenge. Imagine the kind of inhumane torture must have gone on in that underground dungeon!
- How about Katara's ghost story at the beginning of this episode? Never fails to give the chills. Even though the story has nothing to do with the episode itself, it sure as hell sets up the mood.
- Why Hama would do all this? Years of imprisonment in those Fire Nation Tailor-Made Prisons for waterbenders made her snap, and desperate for escape she invented bloodbending. Think about spending years cooped up in a cage, being starved and dehydrated, only being kept barely alive... what made Hama cruel was the Fire Nation's cruelty toward her and her people.
- Although defeated, Hama still gets the last laugh as she says, "My work is done. Congradulations, Katara. You are a Bloodbender." Poor Katara is left in tears.
Nightmares and Daydreams
- The nightmare Aang has after his friends try to "help" him.
The Day of Black Sun, Part 2: The Eclipse
- The War Zeppelins are incredibly intimidating. They're huge, they have snarling faces, shoot cannons, are nearly unassailable because they are crawling with firebenders, and can pretty much only be sunk by a fully realized Avatar- or EACH OTHER. Not to mention they are later used as the Avatar-verse's version of a weapon of mass destruction.
- When Ozai fires lightning at Zuko. Apart from the obvious implications of shooting to kill his own son, the most terrifying part of this exchange is the lightning itself. This is the only time we actually see Ozai bending without the power of the comet. Previously, we have only seen Iroh and Azula shoot lightning; when they did, it took a couple seconds to charge up the energy, and the bolt itself was blue and branched. Ozai's lightning comes out in a split second, deadly focused, and WHITE. That moment alone is enough to cement him definitively as THE most powerful firebender in the series, dwarfing Azula's formidable power and even making Iroh look shaky by comparison. Here is the scene for reference.
Western Air Temple
- There's one in the episode where Zuko joins the Gaang. Zuko spends the entire episode trying to prove himself to the group. No one accepts him except for Toph who wants to give him a chance. She goes to where he is camping for the night, but Zuko mistakes her for an assassin and firebends, burning her feet. The kicker is that she's essentially completely blind. Her feet are useless. What hammered it home is the fear in her eyes as she panics while he desperately tries to explain it was an accident.
- That scene where the Combustion Man continues attacking the Gaang even after Zuko tells him to stop and offers to pay him more if he did. This man is so dedicated to being an assassin, he'll try to kill you even if his employer cuts his contract!
- The Gaang had escaped his clutches twice at that point, the second time embarrassing him by somehow disabling his firebending. It's possible it had become Personal for the man. Which is terrifying in itself.
- The ending where Katara threatens to kill Zuko if he steps out of line is pretty frightening, especially the close-up shot of her face: it looks like she's threatening the audience.
The Firebending Masters
- A glue trap is triggered, trapping Aang and Zuko until they're 'rescued' by the Ancient Sun Warriors. It doesn't sound dangerous on paper, but consider one fact: the room fills itself almost up to the brim with this stuff, with only a grated air hole at the top. Anyone who's trapped would normally race to position themselves up there, and get their head above 'water'... however, when Zuko tried to put the golden egg back, the initial burst trapped him against this grate upside-down... therefore, if Aang hadn't done his one airbending move, flipping him, Zuko would have been face-down in glue for at least several minutes, and suffocated.Zuko: "At least we have air..."
- Though there is some Nightmare Retardant in Aang's ridiculous wide-mouthed expression when he screams for help.
The Southern Raiders
- "I am about to celebrate becoming an ONLY CHILD!" If it wasn't clear before how much of a sociopath Azula is, the utter and terrifying glee with which she says that should be the perfect indicator.
- Katara is downright terrifying. She's out for revenge for who killed her mother and she even used bloodbending on the first man she thought was responsible. She then uses her unparalleled waterbending mastery to control the rain and almost kills the man who is responsible. Suffice to say, Yon Rha was lucky that Katara spared his life even when she had the chance to kill. Just, whatever you do, do not hit her Berserk Button.
Sozin's Comet, Part 1: The Phoenix King
- The whole scene where Aang is unwilling to deal the final blow to the "Melonlord". Sokka walks up and berates him and but Aang explains that it "just doesn't feel right". Sokka grimly pulls out his sword, and the camera pans to Aang's horrified grimace just as we hear a sickening "sqilsh"- but we never actually see the "decapitation". A moment later, the top half of the melon falls and Sokka declares matter-of-factly "There- that's how it's done" while Aang looks like Sokka just killed someone in cold blood. This whole scene is accompanied by the music used when the Gaang has just found out something serious and terrifying. YMMV on this point, but even Momo licking the pink inside of the melon- which is supposed to be comedic- makes one think of the lemur eating a human brain.
- When Zuko tells about how his father plans to use the comet to launch a genocidal campaign against the Earth Kingdom just as his grandfather used it against the Air Nomads, it really nauseated Team Gaang.
- When Team Gaang finds the picture of a baby, they assume it is Zuko. Much to everyone's surprise, Zuko corrects them, noting that the picture is actually of his father. When Suki states that Ozai looks "so sweet and innocent," he adds that said "sweet little kid grew up to be a monster, and the worst father in the history of fathers." Team Gaang looks horrified as to how this innocent-looking child eventually grew up to become the corrupt and war-mongering dictator they're now against.
Sozin's Comet, Part 3: Into the Inferno
- The entire scene where Azula hallucinates seeing her mother in a mirror and talking to her."No. I love you, Azula. I do."
- Not to mention the tortured cello that plays during her Villainous Breakdown, right before she slices her bangs off.
- The utter insane fury she unleashes in her Agni Kai with Zuko is downright unnerving to comprehend.
- Ozai's positively gleeful expression as he is burning the entire Earth Nation to the ground. It's absolutely terrifying.
- Not to mention the horrific tortured-metal screeching sound his fire makes when he's charging it up.
- "Prepare to join them. Prepare to DIE!" Only the Fire Lord could make such campy villain banter terrifying.
- Strangely, a crossover one with Halo. If you know the Halo storyline, you know that the Covenant like to glass planets, essentially what the Fire Lord is doing. Except this time it's not a dogmatic alien menace that's doing this... coupled with the baby pictures earlier, it drives home that this is a human, not so different from his son or his wife or anyone else, doing this. The capacity to do evil doesn't have to be limited to monsters- mankind is capable of becoming those monsters all on its own.
Sozin's Comet, Part 4: Avatar Aang
- Azula's Villainous Breakdown. Straining at handcuffs, and the NOISES she was making. It makes you feel sad for her. Alas, Poor Villain.
- When Aang finally is able to go into the Avatar State and becomes a godly being surrounded by all four elements. Both cool and terrifying.
Avatar State!Aang: FIRE LORD OZAI, YOU AND YOUR FOREFATHERS HAVE DEVASTATED THE BALANCE OF THIS WORLD. AND NOW, YOU SHALL PAY THE ULTIMATE PRICE!.
- What he says to Ozai is unnerving, complete with Voice of the Legion:
- Special mention to the moment where Aang starts to form his battle sphere. He starts by creating five massive streams of fire while letting out this otherworldly roar, not the standard Voice of the Legion accompanying the Avatar State. Coupled with the shot from over Ozai's shoulder of Aang ripping boulders out of the ground, manipulating giant streams of fire, and summoning raging winds, this is the one time where the Avatar State seems less like a Physical God, and more like a terrifying Eldritch Abomination in human form.
- While, yes, Ozai is evil, the way removing people's bending is treated in The Legend of Korra (practically a Fate Worse than Death, with most of the victims begging for it not to happen and visibly traumatized afterwards) makes Aang's use of energybending rather... uncomfortable. The Benders are used to it being an extension of their body, so getting rid of it would be like ripping off somebody's arm... or one of their senses. Or both.
- It gets worse, Amon's method doesn't strip someone of their bending, just their ability to use it. Meaning they have their abilities constantly just out of reach but are functionally perpetually chi-blocked.