Since its run from 2003 to 2005, "Avatar: The Last Airbender," which follows the adventures of 12-year old Aang in his journey to master all four elements, generated massive success in becoming one of Nickelodeon's most popular shows. Its success spawned a sequel series titled "Legend of Korra," which followed Korra, Aang's 16-year old reincarnation. Spanning four seasons and an upgrade in animation with an older cast of characters, the series took on a much more mature tone when compared to its predecessor.

RELATED: The 15 Best Fights from "Avatar: The Last Airbender"

With both now off the air, many fans debate whether "The Last Airbender" or "Legend of Korra" was the better series. Both have plenty of things that made each successful in their own right, but at the end of the day, "The Last Airbender" still stands above "Legend of Korra" in the opinion of this writer. Here are 15 reasons why!

15 BETTER WORLD BUILDING

One of the best parts about fantasy series like "The Last Airbender" is exploring the world at large. When establishing the four nations, the series does a good job of exploring the world around it. With Aang and his friends traveling atop a flying bison, the opportunity is ripe for exploring this world at large. With a lot of time spent within the Earth Kingdom, the series provides enough spotlight with the Water Tribes and flashbacks from Aang's time as an air nomad to give an idea about the different cultures of the world, and how its people interact.

Their stops in various villages provide a diverse amount of perspectives, as no one place they visit is ever the same. While "Legend of Korra" revisits some of the major places while adding new ones like Republic City, the Metal Clan and more of the Spirit World, it falls short of fully capitalizing on the nuances within these realms. It also falls completely on visiting the Fire Nation. Their lack of travel around the world, like Aang and his friends, makes the series' world-building aspect fall short of where it could have gone.

14 ESTABLISHED DIRECTION, ENDGAME

Overarching-Endgame-And-Conflict

"The Last Airbender" made sure it established a strong foundation that it could build upon for a prolonged period by outlining the world and its central conflict within the first three episodes, laying the path for Aang to master the remaining three elements. By episode eight, the pressure is turned up when it is revealed that he only has until the end of summer to master them and defeat Fire Lord Ozai. With that simple yet masterful way of building a compelling story, "The Last Airbender" hooked its audience with a direction that gave each move and decision the characters made more purpose.

No matter what happened, everything was building to the fated final battle between Aang and Ozai. Having that one villain looming as the final endgame made for great anticipation and intrigue, establishing him as the ultimate challenge Aang must overcome. The series built up Ozai as the strongest firebender, yet kept his skills under wraps until his battle in Book Three. This allowed for greater opportunities for development in the young Avatar's journey and gave both him and his friends a central goal to strive towards, something that their Team Avatar successors lacked.

13 BETTER ROMANCE

Better-Romantic-Relationships

If there was one thing "Legend of Korra" got heavy criticism for, it was the way it handled their Korra-Mako relationship. To some, it felt forced and unnatural, lacking any kind of depth. It was an aspect that hurt Korra early on in Book Two and something that Mako's character never really recovered from, as he faded more into the background over the course of the series. This is in stark contrast to Aang and Katara, whose relationship gradually built over the course of the series and culminated in a more satisfying payoff in the series finale.

While some might say it was predictable that they would get together, given Aang's growing feelings for her, their bond was one that was properly cultivated through their experiences. Whether it was through their travels together, waterbending training or eluding capture from Zuko or Azula, their growing (and, as Katara admitted, confusing) feelings towards each other couldn't be questioned as shallow or forced. While Korra and Asami's relationship could evolve in a similar way, there's no denying that "The Last Airbender" handled its relationship aspects in a much different way.

12 MORE SKILLS

More-Skilled-Team-Avatar

With Aang, Katara, Sokka and Toph rounding out the group, "Team Avatar" was a force to be reckoned with, with each knowing their skills and abilities while using them to their fullest extent. Aang, Katara and Toph were the main combatants and heavy hitters of the group, while Sokka was the tactician, often planning the group's many moves and providing them with much-needed direction. Despite being the only non-bender, his value was made clear throughout the series, as his strategies proved to be the difference in taking down the Fire Nation's giant drill and Fire Lord Ozai's airship fleet. The group knew what they were best at and were smart at using each to his or her best advantage.

In comparison, Korra's Team seemed to have no direction, simply running around without any sort of coherent plan or method of attack. Asami's skill lay mainly in operating the technology and she took on a more active role in direct combat, but no one in the group really stepped up as an efficient leader in the way Sokka did. Add in the initial love triangle and the team never really meshed as a functioning cohesive unit.

11 SIMPLICITY

Simplicity of Plot Elements

One of the more underrated aspects of "The Last Airbender" was how its simple plot elements were used so well in its storytelling. With a clearly stated central antagonistic force coupled with its established protagonists and overarching goal, it would have been easy to label the show as generic and predictable. It is here that the series shines, though, by making its plot simple; it is able to introduce new elements one step at a time, providing the material with more purpose that, when expanded on later, has a bigger impact.

Such an example is seen in the Season Two premiere "Avatar State," when Iroh subtly redirects Azula's lightning, a move that is a slight foreshadowing to him teaching the technique to Zuko. The reveal that he found it by studying waterbending is a simple yet unique method that ties the world of Avatar together in a unique way not seen in "Legend of Korra." While introducing new extensions of some of the bending forms, the series could have benefitted from making better use of more simplistic materials, from its multiple and complex plotlines, which were often abandoned at the end of the season.

10 BETTER NARRATIVE

Connected-And-Balanced-Narrative

The benefit of a stated endgame and overarching narrative antagonist in "The Last Airbender" allowed for a steady progression and maturation of the characters, giving audiences an experience to take part in within the journey. The show's three seasons all being interconnected with one another through that one goal made for a more streamlined and cohesive story. Every fight, moment of laughter and lesson learned was all part of their maturation process, and these connected narratives had bigger payoffs in the end, as Team Avatar progressed closer and closer to their fated battle against the Fire Nation.

These connections are demonstrated in an episode like "The Guru," when Aang trains with Guru Pathik to master the Avatar State. During the process, the audiences re-lives all of the joys, fears and emotions that he's experienced up to this point. These scenes are important in demonstrating the importance of the carefully crafted narrative "The Last Airbender" built that from the start. Such experiences are lacking in "Legend of Korra," which seemed more concerned about moving forward and not referencing the importance of past events, which made the narrative feel disconnected.

9 MORE VARIETY

Episode-Variety

Geared towards younger audiences, "The Last Airbender" had a lighter tone when compared to its sequel series. Its episode variety was creative, which allowed the characters to display their individuality in different ways. The Book Two episode "Tales of Ba Sing Se" is the best example of the series' ability to display its characters in such a fashion, as it follows the individuals of Team Avatar, along with Iroh and Zuko, as they each go own about living in the city.

While seeming like a filler episode on the surface, its depth runs much deeper than one might think, as it gives audiences an individual look at the kinds of motivations that define these characters. This is demonstrated perfectly in Iroh. Originally seen as a more insignificant character, the scene in which he honors his deceased son Lu-Ten on his birthday is a wholly touching scene that shows audiences a vulnerable side he hadn't shown before. It also fully exposes and adds more meaning to what his relationship with Zuko truly means, adding depth to their relationship and the complexities within Iroh himself. Having episodes like this are indicative of the series' dynamic episode quality, especially in Book Two.

8 BETTER COMBAT

Technology-Didn't-Hinder-Combat

Taking place 70 years in the future, "Legend of Korra" had technology that advanced to the point of 1900s style automobiles and airships. This extended to combat, as the Equalists made use of electric gloves and even mecha tanks, courtesy of Hiroshi Saito. Unfortunately, it was here that the series may have gone too far in its use of technology, especially in an arena where the fighting style made the franchise so beloved.

By inserting technology like mecha tanks into the series, "Legend of Korra" took away from the spectacular bending battles that made "The Last Airbender" so engaging. Whether it was Katara's graceful waterbending talents, Aang's elusive Airbending or Azula's blue ferocious firebending, the series is at its best and most natural when displaying its bending arts. While showing signs of industrialization in the Fire Nation during Aang's time, "The Last Airbender" was careful in providing the right balance of advancing technology while making sure that bending remained the primary focal point of combat. The technological advancements made within "Legend of Korra" took away from the mysticism of bending to a degree, even after the events of Book One.

7 DEEPER BONDS

Characters-More-United

For all intents and purposes, "The Last Airbender" was an extended road trip, as Team Avatar traveled all over the world. There was never any doubt that as long as the world remained at war, the group would stay united in the path laid before them by Avatar Roku. Unfortunately, it felt as though "Legend of Korra" never had as solid a foundation in comparison, especially when it came to the bonds between its main cast.

By Book Two, Mako was on the police force, Bolin was back in pro-bending with two new teammates and Asami was trying to save her company. The team, while gathering for short spurts of time to fight against the main villain of the season, never had that same bond that the four members from "The Last Airbender" shared; it felt as though they were each wrapped up in their own personal issues elsewhere. While some may attribute that to the show's mature tone, "Legend of Korra" felt as though it was an older shell of its former self. The group lacked that sense of unity and deeper bonds that "The Last Airbender" made such great use of, particularly when it came to their team dynamics.

6 BETTER COMEDY

Better-Comedic-Elements

Comedy is usually never lacking in "The Last Airbender." Whether it was a combination of Sokka and Toph's sarcasm, cameos by the Cabbage Vendor or Iroh's occasional quips and love of tea, the series had the right amount of comedy that allowed it to not feel forced while defining the different comedic elements with its various characters. The show knew where to insert comedy where it was needed and how it wanted to do it, which is more of an art in itself.

"The Legend of Korra" felt as though it could never really find its comedic footing on a consistent basis. Bolin was clearly meant to shoulder a large part of it, with Bumi taking it on in subsequent seasons. The results were often a very mixed bag, as it seemed Bolin never took much seriously and seemed like more of a meager clone copy of Sokka. Bumi never quite captured the craziness of his namesake either, as both performances often came across as being more forced than authentic. Comedy is something that should occur more naturally as a result of the characters' personality, and they often came across as being more annoying than funny.

5 BETTER BENDING

Bending-More-In-Depth

In the Avatar's world, the four forms of bending were based upon four styles of Chinese martial arts. From airbending (Ba Gua) to firebending (Northern shaolin), each style is rooted in its own unique form, which added to the authenticity of the fights and made the art of bending make more sense. It made their fighting style a way of life, especially for the bender.

"The Last Airbender" introduced aspects of bending culture that took audiences deeper into what it meant to be a bender. One example includes firebending, which was seen as evil because of the Fire Nation's actions in the war for 100 years. Their art is given more purpose in "The Firebending Masters," when Zuko and Aang travel to discover sources for their bending. The episode provides Zuko and Aang with sources for their fire while illustrating to the audience that, at their core, no bending is inherently evil, and each style contains its own lore and culture. These cultural aspects of bending were lacking in "Legend of Korra," which, while it expanded certain parts of bending, made for missed opportunities on how bending culture was influenced from a spiritual standpoint.

4 DEEPER MYTHOS

Deeper-Avatar-Mythos

The concept of the Avatar being reincarnated in a set cycle and having the ability to call upon their past lives for guidance and power was a unique aspect Aang made use of on several occasions. It expanded on the Avatar's lore and their deeper connection to the world. One such facet was the Avatar State, which imbues the Avatar with the power of their past lives, albeit with a heavy risk of eliminating the Avatar for good, should they be killed while using it.

The series' treatment of the Avatar State made having mastery over the form a grueling process that shouldn't be underestimated, with Aang having to open seven special chakras to do so. This process is never touched on in "Legend of Korra," skipping the entire process for the sake of resolving the bending conflict following Amon's defeat. After the mixed bag of "Spirits" concluded, the series went further away from expanding the avenues of Avatar lore that could have been further explored, especially when it came to other past lives like Kyoshi, whose actions were instrumental in events that affected both Aang and Katara.

3 MORE DYNAMIC VILLAINS

More-Compelling-Villains

In "Legend of Korra," the villains were the biggest mixed bag of all. Amon, while an interesting villain, given his construction of the Equalists, had a compelling enough story, but a lot of time went untold between his departure from the Southern Tribe and his introduction. There is a deeper person below the surface, but audiences are never exposed to deeper aspects of his character. His ability to take bending, or how he learned it, went unexplained. Zaheer, also missing such development, was easily the series' best villain.  Unalaq was as bland a villain as they come, and Kuvira, who started with such promise, gradually went off the rails in the end.

"The Last Airbender" villains were some of the most compelling to watch, with Azula being a prime example. Flashbacks through Zuko and her vision of her mother shows a mentally unstable person who wanted the approval of the mother who feared her. Even her two friends, Mai and Ty Lee, worked with Azula mainly out of fear. Such subtle writing, coupled with the insight into her character through flashbacks, made her an engaging and fun villain to watch, especially with her firebending skills and calculating mind.

2 BETTER EXECUTED THEMES

Better-Established-Themes

"Legend of Korra" often dealt with various themes of power, privilege and equality. These themes, while cited as a positive for the series, also hurt it in some aspects as the many moving pieces often fell short by season's end. The many interwoven elements often failed to shape characters other than Korra herself. "The Last Airbender" focused on destiny as an overarching theme and how each character's own path is set before them.

Zuko is the perfect epitome of this, as he was destined to help him take down his father and join the gang. Only thing is, destiny can often be a cruel and fickle thing, and "The Last Airbender" showed that avoiding it can lead to disastrous consequences. Such was the case with Zuko, who tried so hard to follow a path he hadn't laid out for himself, eager to win his father's approval and birthright back by capturing the Avatar, that he was led astray and experienced a lot of hardship because of it. Such a simple yet complex theme teaches viewers not to avoid or run away from life despite the hardships, but to fully embrace it and follow your own path.

1 BETTER CHARACTERS

Better-Character-Development

While it did a number of things well, "Legend of Korra" seemed to only be about, well, Korra. Few characters ever get an adequate spotlight of development, and some just remain the exact same the entire series (looking at you Mako). With the exception of Lin BeFong, no other character really gets an in-depth look beyond the surface.

"The Last Airbender" thrives on its character development from its entire cast, from all of Team Avatar to Zuko, Iroh and even Azula. Through the course of the series, viewers not only see Aang mature into a fully-realized Avatar, but they also see the rest of his friends mature in their own right. Whether it's Toph learning to "see" further by bending metal, Sokka learning swordsmanship and realizing his worth to the team, or Zuko's arduous path from villain to hero, the series prides itself on the back of its younger yet more developed characters. Such a nurtured, maturation process that began from the beginning allowed the series to grow with its characters. By its conclusion, there were no questions that all they had been through finally came full circle.

Which Avatar series did you prefer? Let us know your thoughts in the comments!