With this beloved animated series finally returning to Netflix, we look back at the best episodes.

When Avatar: The Last Airbender premiered 15 years ago, no one could have predicted how this cartoon aimed at kids would become one of the greatest animated series of all time. The show explored complex themes such as genocide and imperialism, as well as more abstract questions of fate and destiny, while giving us a world full of rich and vast mythology and a lot of stunning action on par with big-budget live-action movies like Lord of the Rings.

And it all began with a boy trapped in an iceberg, a moody teenager tasked with hunting the boy down, and a looming war that could end everything. In celebration of Avatar: The Last Airbender returning to Netflix, here are the 10 best episodes of the show you can stream starting May 15.

And speaking of things you should be watching, consider listening to GameSpot's weekly TV series and movies-focused podcast, You Should Be Watching. With new episodes premiering every Wednesday, you can watch a video version of the podcast over on GameSpot Universe or listen to audio versions on Spotify, Stitcher, Google Play, and Apple Podcasts.

1. Appa's Lost Days

Season 2, Episode 16

One of the major plot points of season 2 of the show was Aang's sky bison, Appa, getting captured. This led to a major subplot in the series, and Aang's rare moment of succumbing to anger. This episode tells us what happened to the giant, six-legged bison during his time away, and it is devastating.

We follow Appa on a trip of animal abuse, as he's sold to a circus led by a sadistic ringleader, then gets involved in a fight with a wild animal and even encounters the Kyoshi Warriors before getting captured once again. Though it barely features any of our main characters, it's an emotionally-charged episode that shows us a baby Appa melting your heart (take that, Baby Yoda!) when he meets Aang for the first time and that alone makes this one of the best episodes of the show.

2. The Avatar and the Firelord

Season 3, Episode 6

Like Watchmen, Avatar felt like the sequel to a story that was never published, in a good way. Aang's quest is to end a 100-year-old war that began with his predecessor, Avatar Roku, and the show took great pleasure in exploring the history of its world to both provide information and teach lessons.

So when we finally see the origins of the war told through the tragedy of Roku's friendship with Fire Lord Sozin, audiences were in for a treat. What followed was an engrossing episode that showed how the world began and the Fire Nation became the villains of the story, how a powerful friendship was corrupted. We also discover the truth of Zuko's ancestry, and learn the lesson that any person is capable of both incredibly good and bad, and it's up to us to find a balance.

3. The Blind Bandit

Season 2, Episode 6

Pro wrestling comes to the Avatar universe! When Aang needs an earthbending teacher, the team goes to what is essentially a WWE match where they meet the titular Blind Bandit--a 12-year-old blind girl who is exceptionally good at fighting and trash-talking.

The addition of Toph instantly pays off with a hilarious change to the group dynamic, as the earthbender rages at everyone and takes no crap from anyone. Plus, watching such a good fighter turn out to be a spoiled girl from a wealthy and overprotective family who treat her as a helpless and fragile little girl only makes Toph a tougher (ha!) and more entertaining character.

4. The Puppetmaster

Season 3, Episode 8

The one and only time Avatar went full horror movie, this episode is not only spooky, but also deeply tragic. While at a Fire Nation town, the gang hears rumors of local people disappearing each full moon. They also meet a nice, yet creepy old waterbender named Hama who takes Katara under her wing.

In a truly horrific turn, we discover Hama comes from Katara's tribe but was held captive by the Fire Nation and tortured for years. She escaped only when she developed the skill of bloodbending, meaning she's able to control the water inside people and bend them to her will, and has been imprisoning Fire Nation citizens in the mountain every full moon. Besides the use of spooky music and lighting to craft a horror atmosphere, the episode added to the show's mythos by showing us that there are different types of monsters out in the world.

5. The Storm

Season 1, Episode 12

This is the episode where Avatar went from a good but goofy kids show with broad humor, to a fantasy epic with fully fleshed out characters. The episode deals with our characters stuck in the middle of a storm, so they decide to tell some stories, resulting in the first time we see the backstory of our hero, Aang, and our villain, Zuko.

In a single episode, The Last Airbender makes Aang a flawed and more relatable character who isn't above running away from responsibility because he'd rather play with his friends. Likewise, we discover that the moody, annoying villain Zuko is a tragic victim of tradition and abuse, exiled from his home and sent off on an impossible mission because he dared speak out of turn. This was a pivotal moment that made it clear we were seeing more than broad archetypes, and it set Zuko on a path to become one of the best characters in modern fiction.

6. The Ember Island Players

Season 3, Episode 17

The clip episode is a staple of TV. Lots of comedies, from The Simpsons and Friends, to Frasier and Community, include a clip episode to save on the budget. So it came as no surprise that Avatar would also have one, but thankfully this is not most shows. Instead of simply re-using old clips to save on budget, the show gave us a recap of the entire show in the form of a fictional play recounting our heroes' adventures.

The Ember Island Players pokes fun at everything from the dropped or unexplained plot points (Jet's death, anyone?) to the characters' more annoying traits, like a constantly-sobbing Katara and Sokka's obsession with food, to even the show's fandom itself (via a reference to the most popular 'ship in the show). It may feel weird to have this "wacky, time-wasting nonsense" (to quote Sokka) right before the explosive finale, but it was so well executed it served as a nice breather before the finale.

7. The Crossroads of Destiny

Season 2, Episode 20

The Empire Strikes Back of Avatar episodes, this was the show's darkest hour. Aang gets a vision that his friends are in danger and leaves his training to help them, but it turns out to be a trap set up by the villain. The Earth Kingdom's capital is finally conquered by the Fire Nation, Zuko betrays his uncle and joins Azula to fight team Avatar. Oh, and Aang almost dies. What a dark way to end your season.

And in addition to the good guys losing miserably, we also get some hints of future team-ups, and Azula turning into Cersei Lannister, mad with power. This is also one of the most climactic final showdowns in the entire show, throwing new bending abilities at the audience like an armor made of crystals, and dragon-like firebreathing.

8. The Tales of Ba Sing Se

Season 2, Episode 15

The Tales of Ba Sing Se is an anthology episode with something for everyone. There's Sokka entering a haiku rap battle, Katara and Toph having a girl's day out, and Zuko going on a date. Even Momo gets his own little story, but the episode is mostly remembered for the heart-wrenching Tale of Iroh segment.

Despite his past as an honored military leader, Uncle Iroh served as kind of the Mr. Rogers of Avatar, an extremely kind man who saw the worth in every life and culture. The episode encapsulates his character in just a few minutes, as we see Iroh going around Ba Sing Se, helping everyone he meets, including a mugger. Then we see Iroh travel to the top of a hill at sunset and make a shrine to his late son, Lu Ten, before he breaks down while singing a song for his son's birthday. The song itself is enough to pull at your heartstrings, but the final dedication to Mako, Iroh's original voice actor who passed away before the series ended, makes this a guaranteed tear-jerker, and proof of the show's ability to craft a powerful story in a short amount of time.

9. Sozin's Comet

Season 3, Episodes 18-21

Allow me a bit of cheating in adding the four-part season finale, which is not only one of the best endings to a TV show ever, but has some of the best moments ever committed to animation. We get philosophical discussions with past Avatars about when it is just to kill someone, reunions with old friends, much needed moments of levity like Sokka tricking a ship's crew to head to a trap with the promise of a birthday party, and also the fight scenes.

Avatar has some of the best fight scenes in Western animation, and this finally shows the best of what the show can offer. There's the grander scale battle to reclaim Ba Sing Se, with hundreds of fighters and vehicles, and Sokka and Toph taking down an entire fleet of airships. Then there's Zuko fighting Azula in what can only be described with a chef's kiss, and the final showdown between Aang and the Fire Lord, a nearly 14-minute fight where every element gets used to devastating effect. Everything in this episode is running on all cylinders, and the use of an orchestral score makes this feel like a grand cinematic event.

10. Zuko Alone

Season 2, Episode 7

Avatar's strength wasn't only in its dynamic fight scenes, but in its character-driven episodes, and this is one of the best ones. Where some villains get redeemed by doing just one good action and then dying, Zuko's path to redemption was long, arduous, and very awkward.

Zuko's journey begins in this neo-Western episode where the exiled Fire Nation prince tries to protect a young Earth Kingdom boy and his family from local soldiers bullying them. No matter how much Zuko helps them, when he reveals his identity, he is instantly rejected by the family he saved. From here on out, Zuko starts trying to carve an identity out for himself that's separate from his legacy and background.