Since their respective debuts, "Avatar: The Last Airbender" and  "Legend of Korra" gained massive success. Set in a fantasy world where characters have the ability to manipulate the elements of air, water, earth and fire, both series made their mark on audiences. From their unique blend of action and comedy to their mature themes and likeable characters, the series was unlike any before it.

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However, since "Legend of Korra" ended in 2014, fans have been clamoring for more from the world of Avatar. While its predecessor spawned a number of comics after its end in 2008 and "Legend of Korra" is getting its own comic, the franchise still contains a number of untold stories that would be worth telling. Fortunately, CBR is here to help sort out the stories that are left to tell and the ripe opportunity to bring excitement back to the fans of both series.

15 ZAHEER

Zaheer flying in The Legend of Korra.

One of the most celebrated villains from "Legend of Korra" and the main antagonist of Book Three, Zaheer became a unique threat by gaining Airbending abilities as a result of Harmonic Convergence. A member of the Red Lotus, Zaheer was knowledgeable in Air Nomad culture and was skilled in the art despite having just learned it. As popular as he was, he remained a mystery. How did he come to learn so much about Air Nomad culture? How did he join the Red Lotus? What were his skills like as a non-bender? The fact he was kept in a prison in the sky likely speaks volumes.

A Zaheer spinoff would answer a ton of these questions while also giving fans a peek into what motivates him as a character. For all the good he did as an antagonist, he left too many open questions. Even in Book Four, he managed to aid Korra in her recovery.  From his crusade to becoming a part of the Red Lotus to meeting his team members and becoming engrossed with the Air Nomads would be an engaging read for any Avatar fan who couldn't get enough of Zaheer in Book Three.

14 KUVIRA

Kuvira from Legend of Korra

Another villain in "Legend of Korra" who started out strong but faded out near its end, Kuvira was a villain who was briefly named at the end of Book Three but fully came into her own in Book Four, where she amassed her own army in an attempt to expand the Earth Kingdom. While viewers got a brief look at her motivation following her defeat against Korra, it felt very rushed and lacked the genuine impact that it could've had. A spinoff of Kuvira could change that.

Not anyone can rise through the ranks of the Metal Clan the way Kuvira did. Her skills were such that she was able to match a fully-recovered Korra in battle while possessing the command and respect that garnered many to her side. Having been abandoned by her parents and raised by Suyin as her own child, Kuvira had an interesting background that could delve further into the psyche of her character. Given the state of the Earth Kingdom during this time, such a spinoff could add a much-needed layer to her character that she lost in Book Four.

13 KORRA'S AVATAR SUCCESSOR

Earthbending Avatar

While it essentially amounts to a sequel series, the ending of Book Four virtually calls for the next Avatar to take their place in the cycle. Of course, that would require Korra's death to occur, but the possibilities for this next take on the Avatar would be endless.

Thanks to the Earth Queen's death and Kuvira's rise, the Earth Kingdom was left in an unstable state. Would it not be a fun take to see the next Avatar be some sort of abandoned child or rogue? Have them be a bit more mischievous in ways that Aang and Korra weren't? Having this child grow up in such an unstable time for the Earth Kingdom would create a different kind of pressure on this Avatar, especially if they don't come from a well-meaning background the way Korra and Aang did. The Earth Kingdom is huge, and there are always opportunities to create new places to explore within it and new challenges to overcome. Just as Aang had trouble with earthbending and Korra had trouble with airbending, this Avatar could have trouble waterbending. It would be fun to see just what new elements this Avatar could bring to the table.

12 MAKO AND BOLIN

Mako and Bolin

Two of the three mainstays of Korra's Team Avatar, Mako and Bolin were two characters that gradually saw their roles lessened as the focus shifted elsewhere. They were not without skill, as Bolin realized he was a lavabender and Mako can bend lightning. Despite this, both lacked in proper character development and a spinoff would do them a world of good, especially Mako, who seemed to serve as little more than a brief love interest for Asami and Korra.

With their parents murdered and having to live on the streets, further exploring Mako and Bolin's time in the streets and further exploring their family would be worth looking into. Given that one of their parents were of the Fire Nation, potential connections could be made there as well. Charting the course from their parents' murder to their joining the Fire Ferrets would be an engaging tale of brotherly bonding. It would give Mako's character the time it didn't receive in "Legend of Korra" and show fans they can be more than a brooding face and a jokester. Their connection towards their family and each other should be better showcased in a spinoff where it can get the proper attention it deserves.

11 AANG'S CHILDREN

Bumi, Tenzin and Kya from Legend of Korra

If Book Two of "Legend of Korra" did something well, it was the proper introduction of Tenzin's siblings in Bumi and Kya. Each of the siblings demonstrated their own personalities and the series hinted at their various backgrounds. The trio was a pleasure to have on-screen together, and it would be a greater pleasure to provide them siblings a spinoff of their younger days together.

While the three get along with one another, Bumi and Kya were found to be more distant from their father, given his Avatar duties and doting on the lone airbender in Tenzin. With Kya being a waterbender and closer to her mother, Bumi was left as the lone non-bender having to prove himself. While he went on to become a decorated soldier, he always harbored doubt as to whether he lived up to his father's name, even apologizing that he wasn't an airbender like he wanted him to be. Following the siblings' childhood and individual journeys from Tenzin's progression through Republic City to Kya's world travels and Bumi's time in the United Forces could make for a fun story that further demonstrates the bond between the trio.

10 ADMIRAL ZHAO

Admiral Zhao and Tenzin

One of the primary antagonists in "The Last Airbender" throughout Book One outside of Zuko, Admiral Zhao was a commanding officer who quickly rose through the ranks and became one of Aang's major adversaries for much of Book One. He shared a strong dislike for Zuko and a lust for power as he sought to make his name known through Fire Nation history.

A spinoff on Zhao could not only focus on his background and upbringing in the Fire Nation, but also on his time spent with Jeong Jeong and his time spent in Wan Shi Tong's library where he discovered the secret of the Ocean and Moon spirits. Zhao's obsession to be the best had to come from somewhere, and the roots of it were planted long before he discovered the library. His obsession for power and glory eventually led to his downfall and subsequently becoming trapped in the Fog of Lost Souls, where he has become mentally insane and continually stuck on reclaiming Aang to return to his former glory. A spinoff on Zhao could make for an intriguing look on life in the Fire Nation military and his path in starting to climb its ranks.

9 DAI LI

Dai-Li from Avatar The Last Airbender

Known as the secret enforcers within Ba Sing Se, the elite group of Earthbenders serves directly under the ruling Earth King/Queen, protecting them and serving a variety of special functions. From enforcing laws to carrying out secret missions doled out by the ruling Earth monarch, the agents are absolutely loyal to the crown above all else. Though, as seen in "The Last Airbender," they are not invulnerable to manipulation, having been taken control of by Long Feng and Azula.

Created by Avatar Kyoshi for the purpose of maintaining the city's culture, the Dai Li became a major opposing force that became the main reason Azula took down Ba Sing Se. A spinoff of the organization would gain insight into the more in-depth means of what it takes to become an agent. It's clear that they undergo immense training and undertake harsh missions for the sake of the monarch, and they've only become more corrupt and unstable as time went on. While "The Last Airbender" gave hints towards their training methods, it would be interesting to see the group at its inception and how such an organization grew out of control.

8 FIRE SAGES

Avatar Fire Sages

The religious equivalent of the Air Nomads for the Fire Nation, the Fire Sages are a group that do not have much of a role in the franchise. They are mostly known for identifying the Avatar once they're born within the Fire Nation. How exactly they do so is unknown. While the group had been forced to serve directly under the Fire Lord during the Hundred Year War, it was later directed back to its original goal of serving solely the Avatar while acting as the Fire Nation's religious leaders.

Out of all four nations, the Fire Nation is often one of the lesser explored or expanded upon, especially when it comes to their cultures and beliefs. One of the industrially advanced nations, focusing on the actions of the Fire Sages would be a great opportunity to learn more about the culture and histories of the Fire Nation that remains unknown. The Fire Sages are well acclimated with various histories of the world and their nation, and following the path towards joining their ranks would be a unique turn that offers a deeper delve into the Avatar mythos from a different point of view.

7 ORIGINAL AIR NOMADS

Air Nation from Avatar The Last Airbender

A culture that built their large temples in the North, South, East and West, the Air Nomads were a group that were largely wiped out by Fire Lord Sozin, who sought to kill Aang in order to expand the Fire Nation's rule. While a new generation of Airbenders was later restored as a result of Harmonic Convergence, the original culture and structure of the Air Nomads were never expanded upon. A prime opportunity exists to delve deeper into their culture.

Naturally peaceful men and women, Air Nomads often valued life and were practicing vegetarians. Because of their peaceful nature, they rarely partook in anything remotely violent and were largely spiritual. While they didn't have an official military, Aang states that Sozin only beat them by ambush, implying that they have an adequate ability to defend their lands when threatened. Exactly how each of the temples functioned in comparison to one another remains unknown, as does the order and hierarchy of how they operated. A spinoff detailing the Air Nomads back in Aang's time prior to the arrival of Sozin's comet would give some much-needed lore to the Avatar's world and provide a crucial piece in what it means to be an Airbender.

6 IZUMI

Firelord Izumi from Legend of Korra

Introduced oh-so shortly in "Legend of Korra," Izumi is the daughter of Zuko and the reigning Fire Lord of the Fire Nation. Outside of her apparently calm and reserved demeanor, fans found out next to nothing about her. Heck, her mother wasn't even identified and she didn't make an appearance until Book Four.

Thanks to their genocide of the Air Nation and their oppressive actions in the Hundred Year War, the Fire Nation has a very dark history. Restoring that trust and changing the tune of an entire country is no small task. A spinoff with Izumi would be an intriguing look into how much the Fire Nation changed under both her father's rule and the pressure she had to deal with given her family's past role. "Legend of Korra" didn't give much of a peek into the state of the Fire Nation, outside of the fact that Izumi doesn't rush to mobilize the military given their actions in the past. Given how complex Zuko's childhood was, Izumi's has a chance to be interesting as she becomes tasked with rebuilding the emotional state of the Fire Nation and re-establishing trust throughout the world.

5 AVATAR KYOSHI

Avatar Kyoshi Earthbending

Outside of Avatar Roku in "The Last Airbender," Avatar Kyoshi was the most featured past incarnation to have the most impact in the story. Having created Kyoshi Island by literally splitting the continent and becoming the inspiration for a group of female warriors that defend it, Kyoshi is a perfect character who deserves a spinoff more than anyone.

In the series, Kyoshi appeared as a very well-meaning yet hardline and aggressive Avatar who wasn't afraid to use force. Being the first known Avatar to technically kill someone, she is willing to do whatever actions it takes for the greater good. She is also responsible for the creation of the Dai Li, which would be a perfect opportunity to link the two together in regards to her purpose and intent behind its creation. Kyoshi's popularity is part of what resulted in the creation of "Legend of Korra," but she fully needs the limelight given the impact and legacy she left behind throughout the entirety of the Earth Kingdom. Her unique fighting style using fans would also make for a different combat style fans haven't seen the full extent of from a master like herself.

4 KING BUMI

King Bumi earthbending in Avatar The Last Airbender

Aang's old friend growing up prior to the Hundred Year War, Bumi was a "mad genius" who was arguably the most powerful Earthbender in the entirety of "The Last Airbender." Despite this, fans didn't get background information as to whether Bumi's family was nobility or if he simply climbed the ranks in order to earn his title as ruler of Omashu.

Chronicling the life of a mad genius like Bumi would no doubt be a fun and thrilling ride. Despite his crazy personality, he holds vast knowledge of many subjects, from Earthbending to tactical strategy. This was demonstrated when he purposefully remained a prisoner within Omashu until the solar eclipse occurred and subsequently took the city back by himself. Even with his advanced age, Bumi's skills as an Earthbender are such that, despite his body being fully restrained, he could earthbend with his face and neck alone. Bumi's close relationship with Aang is also such that the latter named his oldest son after him. Following Bumi's progression from Aang's disappearance to his time and rule as king would make for a rather engaging tale of a mad genius Earthbender who somehow became king.

3 RED LOTUS

Red Lotus symbol from Avatar

Up to this point, next to nothing is known about the Red Lotus. Like their counterparts in the White Lotus, they largely operated in secret, but the reveal that antagonists like Unalaq and Zaheer were prominent members were shocking. With a goal to take down the Avatar, live alongside the spirits and topple world leaders and governments, the organization is one that is ripe with opportunity for spinoff exploration.

Essentially the Hydra of the Avatar Universe, the Red Lotus, up to this point, has only had five of its members revealed. Sticking to the shadows, who's to say that more prominent leaders and figures aren't among their ranks in a similar fashion like Hydra agents? Touching further upon the organization's founding, how it recruits its members and how it got its hands on powerful people like Zaheer and Unalaq would be quite a dive into the more darker aspects of the Avatar universe. This darker dive was one of the aspects that made Book Three of "Legend of Korra" such a success, and seeing the operations from within an enemy's ranks would make for compelling storylines and insight that wouldn't be found anywhere else.

2 WHITE LOTUS

Iroh leads the White Lotus in Last Airbender

A secret organization revealed in "The Last Airbender," its purpose fell outside of the influence of any nations, as it originally acted as a means to share knowledge and information despite the origins of its members, who came from each of the nations. They remain neutral from any one nation, and only take action in certain circumstances, with the liberation of Ba Sing Se being such an example.

Since then, the organizations' role has been slightly expanded, as it is their duty to help train and protect the Avatar. Despite such a role, little is known about its membership, how people join, how it was founded or even what such "knowledge" it is they possess. A spinoff of the White Lotus would serve as a deeper look into an organization that has been around for decades, perhaps centuries, and has never gotten a proper explanation or any kind of history. The White Lotus could also provide a unique perspective away from the prying eyes of the four nations and allow viewers to see a different, more secretive side of the Avatar's world they've never been able to see before.

1 IROH

Iroh from Avatar

The character who most needs a spinoff and quickly became one of the most interesting characters once viewers learned about some of his history, Iroh offers a bundle of storytelling opportunities that were only hinted at throughout the series. Whether its his childhood and relationship with Ozai, his first venture into the Spirit World, his long-standing siege at Ba Sing Se and the loss of his son or his meeting with the Sun Warriors, Iroh has a wealth of material to choose from.

According to Zuko, he has a complicated past and wasn't always the most benevolent man that he eventually became. While he made a pleasant appearance in "Legend of Korra" and helped the young Avatar get back on the right track, fans need to know more of Iroh's rich history within the Fire Nation and his progression to what he would become. Of course, that's without touching on his skill as a Firebender, displaying an ability to not only wield lightning, but also creating a technique to successfully redirect it. Seeing Iroh at the height of his combat prowess would be nothing short of astounding.

What did you think of our list? What stories would you like to be told from the Avatar mythos? Let us know in the comments!