A show like Avatar: The Last Airbender doesn't come around very often: the series' unique balance of being marketed for kids while being wise and mature enough for teens and adults not only made it one of the most popular series of all time, but also one of the highest-rated.

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While the first and second seasons certainly boasted ratings worth bragging about, it was the third and final season of ATLA that truly blew fans, audiences, and critics away, as Aang and the rest of Team Avatar finally faced their destiny.

Day of Black Sun, Part 1: The Invasion, Episode 10 (9.1)

Fair warning: there are a lot of multi-part episodes on this list. Team Avatar might not have had the Earth Kingdom's army, but they still had the advantage of the solar eclipse leaving the Fire Nation defenseless. So, during this episode, fans were ecstatic to see the return of most of the characters/allies that Aang and the gang had met through their travels.

After assembling a battle plan, the rag-tag group of rebels attacks the Fire Nation with Aang going off alone to face the Fire Lord—only for Aang to find the entire palace-city abandoned.

Sozin's Comet, Part 1: The Phoenix King, Episode 18 (9.1)

avatar the last airbender

With Sozin's comet approaching, Zuko—along with the show's fans—was thrown for a loop when Aang revealed that he was going to face the Fire Lord after the comet came,  only for Zuko to reveal his father's horrific plans for the day of the comet.

Buckling down, Aang begins training even harder to master the elements. However, he mentally grapples with the prospect of having to kill the Fire Lord. In the middle of a dream-like state, Aang wanders off into the night and swims to an island... which, come morning, is no longer there, forcing the rest of Team Avatar to try and find Aang before the comet arrives.

The Puppetmaster, Episode 9 (9.2)

avatar the last airbender

There are only two types of people in the world: those who were terrified by this episode, and liars. When the group shows up in a mysterious fire-nation town where people have been disappearing into the woods, they immediately assume it's spirit-shenanigans.

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However, after meeting Hama, a water-bender in the village living in disguise who reveals to Katara that she is a master "blood-bender," the kids realize that she's the one who has been making people disappear. Katara and Hama have an epic water-vs-water battle that ends with Katara having to blood-bend Hama in order to keep her from killing Aang and Sokka.

The Firebending Masters, Episode 13 (9.2)

Aang and Zuko back to back in ATLA

Fans had longed to see Zuko switch sides and join Team Avatar, and they finally got their wish, only to be let down when Zuko "loses" his firebending abilities. Because of this, Zuko and Aang travel to the ruins of the Sun Warriors, an ancient civilization of firebenders.

However, upon arrival, Zuko and Aang are apprehended by the current members of the Sun Warrior tribe. As a test, Zuko and Aang must face the "firebending masters" to see if they are worthy, only for the masters to be revealed as two monstrous dragons. Luckily, they deem Zuko and Aang worthy, just as they did to Iroh, and pass the secrets of firebending on to the two of them.

The Boiling Rock: Part 2, Episode 15 (9.3)

The gaang in Avatar The Last Airbender

In the episode prior to this one, Zuko and Sokka made their way to a high-security Fire Nation prison in order to save Sokka's dad. Not only did they find Sokka's dad, but they also found Suki, as well.

This episode dealt with their eventual escape from the prison, but it was soon hindered by the arrival of Azula, Mai, and Ty Lee. The two groups face-off against each other in a battle atop a gondola as they try to escape, only for Mai to turn on Azula and help Zuko get away. As a result, Ty Lee turns on Azula, and Azula imprisons her two closest allies.

Day of Black Sun, Part 2: The Eclipse, Episode 11 (9.4)

Aang and his allies in Avatar the Last Airbender

While the first episode of this two-parter dealt with the invasion, this episode dealt with the eclipse itself. After Aang discovers the palace empty, he goes with Toph and Sokka to an underground bunker to try and locate the Fire Lord. Unfortunately, they run into Azula instead, who maniacally manages to evade their clutches despite not being able to bend and makes them waste the entire eclipse.

As a result, the Fire-Nation regains the advantage and defeats the rebels incredibly easily, forcing Team Avatar to retreat while everyone else remains behind as prisoners. The one high note of the episode came when Zuko finally turned on his father and decided to join Team Avatar.

The Avatar and the Firelord, Episode 6 (9.5)

avatar the last airbender

The episode that arguably presented the most plot-holes for the rest of the series—seriously, it creates a ton—was nevertheless so bad-ass and compelling that audiences openly forgive them. The episode flashes back and gives fans the backstory of Avatar Roku, Fire Lord Sozin, and how the 100 Year War began.

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As it turned out, Sozin and Roku were friends growing up, but their opposing views on the world/Fire-Nation ultimately led to Sozin letting Roku die in order to move forward with his invasion plans. Then, in an incredibly shocking twist, it's revealed that Avatar Roku was Zuko's great-grandfather (on his mother's side).

Sozin's Comet, Part 2: The Old Masters Episode 19 (9.5)

Team Avatar during the Sozin’s Comet saga in Avatar The Last Airbender

Nothing but the finale from here on out. After waking up on the strange island and not knowing where he is, Aang takes time to meditate and ask his past lives for advice on what to do about the Fire-Lord, the overall consensus being death.

Meanwhile, not knowing where Aang is, the rest of Team Avatar goes looking for Iroh, only to arrive at Ba Sing Se where they encounter all of their old masters from the prior seasons. In the end, it's revealed that the island Aang was on was actually a lion-turtle... and the creature then gives Aang the wisdom and power that he needs in order to face Ozai.

Sozin's Comet, Part 3: Into the Inferno, Episode 20 (9.8)

Sokka, Toph, and a girl looking up in shock in Avatar: The Last Airbender.

The comet arrives, and Team Avatar faces their destiny as Sokka, Toph, and Suki try to stop the Fire-Nation air-ships, Zuko and Katara confront Azula, Iroh, and the Old Masters liberate Ba Sing Se, and Aang faces-off against the Fire Lord.

Action-packed and full of thrilling, eye-catching sequences, the episode ends with Toph, Sokka, and Suki trying to bring down the last of the ships, Azula trying to shock Katara with a cheap shot and Zuko taking the hit, and Aang doing everything he can to fend off Ozai, seemingly fighting a losing battle.

Sozin's Comet, Part 4: Avatar Aang, Episode 21 (9.9)

Aang fights against an enemy in ATLA

It all came down to this. After holding off an onslaught of attacks from Ozai, Aang manages to unlock his 7th chakra and enters the Avatar State, effectively taking Ozai to the cleaners. However, rather than kill the Fire Lord, Aang uses the knowledge that he gained from the lion-turtle and takes Ozai's bending away, instead.

Meanwhile, Katara proves that she's the baddest waterbender alive and takes down Azula on her own, healing Zuko afterward and saving him in the process. The comet leaves, the war ends, Zuko becomes Fire Lord, Aang and Katara get together, and thus ended one of the greatest television series to ever exist.

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