Tropes A to H (Big Bad, Chekhov's Gun, Deconstructed Character Archetype, Foil, Foreshadowing, Hidden Depths) | Tropes I to P | Tropes Q to Z (Red Oni, Blue Oni, Running Gag, Ship Tease, Shout-Out, Shown Their Work, Wham Episode)
- Even from the get-go, there is a subtle difference in the sound of firebending between Iroh and other Firebenders, and his attitude is far calmer and more patient than the emotional style of everyone else around him. Iroh's firebending sounds more like a great rushing than the controlled explosions of other firebenders, and he places great emphasis on basics and breath. Because he had already visited the Firebending Masters and learned how to properly firebend rather than to firebend through rage and anger, as other firebenders have over the past one hundred years. When Zuko and Aang learn the same, the sound of their firebending changes as well.
- Schematics for the drill from the middle of the second season appear during "The Northern Air Temple" in the first.
- When Avatar Roku is about to destroy his temple in his eponymous episode, he lets only the loyal Fire Sage and Zuko go free. The former seems pretty obvious but the latter is a bit baffling at that point. He’s just a bratty prince. Zuko later learns that Roku is his great-grandfather.
- Katara's overall waterbending potential is alluded to early in the first episode when she rips an iceberg apart (and frees Aang) without even realizing it as she blew her stack over her brother's sexism.
- We see in "The Chase" that attacking/blaming Appa gets Aang really angry. When Appa is gone, he goes for the full Heroic BSoD.
- During the flashback showing when Zuko was brutally scarred by his own father during an Agni Kai you catch a quick glimpse of the audience, most of whom are watching with cold indifference save for three. Uncle Iroh is horrified, showing him to pretty much be the only one in Zuko's life who actually cares for him. Zhao has a self-satisfied smirk, hinting he's going to be an enemy of Zuko. Finally there's an as-of-yet unintroduced girl watching with a cruel smile, letting you know she's going to be bad news: she pops up much later as Zuko's sister Azula.
- When Azula is introduced, we see her practicing lightning-bending. She successfully pulls off the difficult firebending move (and is the first to demonstrate it in the series; only two others know how to do it), but with one hair out of place. When this is pointed out to her, she gets angry and freaks out slightly, saying that "almost perfect isn't good enough." Later in the series, when she actually miscalculates on something significant, she completely loses it and starts what is likely the most epic Villainous Breakdown in the history of fiction.
- While we're on that subject, in "The Drill," Mai flat-out refuses to jump into the rock slurry after Katara and Sokka, saying "She can throw all the lightning she wants at me. I'm not going down there", showing that her sense of disgust outweighed her fear of Azula. And, as we find out in "The Boiling Rock," so did her love for Zuko.
- Also in "The Drill", Aang states he really wishes he were a metal bender. Toph invents metal bending a few episodes later.
- White lotus tiles sure do come up often. Especially around old men. They turn out to be the symbol of the Order of The White Lotus.
- In "The Boiling Rock, Part 1", the Warden says he'd rather fall into the boiling lake surrounding the prison rather than let its record be blemished. In Part 2, he proves he's not just blowing steam.
- A portrait of the lion turtle appears in Wan Shi Tong's library. And the music (complete with Buddhist chanting) which plays when Aang meets the turtle also plays when he is briefly possessed by Roku at the Fire Temple, setting up the connection between the turtle, the Avatar, and the Spirit World.
- When searching Hama's house in "The Puppetmaster" the Gaang stumbles upon a closet full of marionettes. This foreshadows Hama's bloodbending ability, with which she controls peoples limbs, jerking them around like puppets. The episode title also foreshadows this.
- In "Siege of the North Pt 1" before the fire nation attack, the northern Chief gives a speech calling his family knowing that "some faces will disappear from their tribe" we have a quick focus of Yue, Master Pakku and Hahn. In Siege of the North Pt 2 Yue, sacrifices herself to revive the moon, Hahn is thrown off a platform after his failed attempt of attacking Zhao and Master Pakku leaves to the Southern water tribe at the end.
- At the end of "The Beach," Azula gets the Mood Whiplash/Funny Moments line of "My own mother... thought I was a monster. She was right, of course, but it still hurt." During the finale, the thing that finally sends her over the edge of madness is a hallucination of her mother.
- When they fight the melonlord in "The Phoenix King", they group up the same way they do in the final battle: Aang is alone, Zuko is with Katara, and Sokka is with Suki and Toph.
- While flying through clouds in an early episode, Aang notes how they are made up of water. The plan to solve the conflict of "The Fortuneteller" involves Katara using her waterbending on clouds, together with Aang's airbending.
- In "The Storm" alone, we have Zuko caring about the lives of his people more than his father, Master Gyatsu messing around with Aang with a White Lotus tile, and Iroh redirecting lightning. Bear in mind this is halfway through Book 1: Water.
- Also, that blimp that gets shot down in "The Northern Air Temple"? The Fire Nation takes its tech to build a much larger one in the finale.
- An extremely subtle example; in "The King of Omashu", Bumi warns Aang that defeating Ozai will take extremely out-of-the-box thinking. See The Cloud Cuckoolander Was Right, above, for how thinking like a mad genius helped Aang in his adventures.
- Another subtle one from Bumi: he chides Aang in their duel, saying "Typical airbender tactic; avoid and evade," and that Aang will have to punch back sometime. Toph ends up repeating his assessment when Aang's focus on looking for a way out or a creative solution hampers his earthbending: to really learn the essence of earthbending, Aang has to learn to face problems head-on. Plus the fact that he knows how Airbenders typically fight foreshadows the reveal that he was Aang's old friend all along, since he's one of the few people alive who remembers what airbenders were actually like.
- At the end of "The Blue Spirit", Aang wonders out loud if he and Zuko might have been friends under different circumstances. Zuko immediately attacks him, but when he returns to his ship and goes to bed, he pointedly rolls over so that his back is to the Fire Nation's banner.
- Jeong Jeong's warning words that "Without a bender, a stone doesn't throw itself, but fire spreads" is unknowingly repeated in its spirit by Zuko when he warns Aang that if he isn't careful, the fire will burn him, signaling that old men do all know each other and that Iroh and Jeong Jeong are both members of the White Lotus.
- And before Jeong Jeong's warning, one of the earlier things we're told about firebending comes from a soldier in "Imprisoned", who talks about how fire can be hard to control. Besides being a thinly-veiled threat, it foreshadows the point made by Jeong Jeong that Aang learns firsthand.
- Zuko's dream in "The Earth King" is this, illustrating having to make a choice between his uncle, the red dragon (good), and Azula, the blue dragon (evil) two episodes later. in the next season, he and Aang meet the Firebending Masters, who turn out to be a red and blue dragon. Neither of them are evil, however.
- When forced to leave the invasion force behind on the Day of Black Sun, Sokka and Katara hug their father, with Sokka commenting that they "won't be apart for too long this time". A few episodes later, Sokka and Zuko break him, as well as Suki and an additional prisoner, out of the Boiling Rock.
- Ty Lee's chi blocking paralyzes people (and temporarily prevents benders from accessing their powers, although it's unclear if it's actual depowering or they just can't bend because they can't move). Combustion Man is stopped when a pebble strikes his tattoo, disrupting his chi flow and disabling his combustion abilities. One of Azula's lightning strikes manages to hit Aang exactly in a chakra, cutting him off from the Avatar State, and he doesn't get it back until a rock strikes his scar. These are early clues that show it's possible to manipulate someone's energy, even to the point of turning off their bending, and cause long-term, serious changes. Just like Aang does to Ozai in the finale.
- The opening of every episode features a shot of the last Avatar (Roku) standing among pillar-like mountains with the orange setting sun behind him. The Final Battle between Aang and Ozai takes place among a sea of stone pillars with the sky painted orange from Sozin's Comet. That's right, they foreshadowed the setting of the story's climax from the very first episode.
- When Azula tells the Earth King "it's terrible when you can't trust the people who are closest to you" in "The Guru", Mai and Ty Lee very subtly glance toward each other
◊. This foreshadows that Mai and Ty Lee will eventually turn on Azula in "The Boiling Rock", and the fact that Azula couldn't trust the people closest to her leads to her truly magnificent Villainous Breakdown.
