The Lack of a Real Relationship between Aang and Ozai
The Punching the Scar on Aang's back to jumpstart the Avatar State
And Everything to do with the Lion Turtle but more specifically Energybending
People often call out The Legend of Korra for overusing Deus Ex Machinas to resolve their plot points but many seem to forget that The Last Airbender is guilty of this too. Koyzilla in book 1, the Healing Water in Earth and the Lion Turtle in Book 3. These things have almost as little buildup as the DEM in TLOK and are just as contrived as the ones in TLOK.
But what bugs me most about Energybending is how little it's used in the series. Really it's only been used twice between both Airbender and Korra and has basically been forgotten since the finally of Korra.
At this time one of the stories I'm working the hardest on is an Avatar Series that I'm hoping to pitch to Avatar Studio in the near future (Working title is Spirit Hunter and it's kinda Avatar's version of The Witcher, The Mandalorian and The Last of Us). And one thing Ive written in this series is the inclusion and expansion of Energy/Spiritbending and how it can work in this series.
The way I have it is Spiritbenders are basically glass cannons as they are possibly the most powerful Benders in the world for a number of reasons. As shown with Airbender and Korra an Spiritbender can takeaway or give someone bending powers but they can also Eat someone's life force or transfer energy around and can even borderline read someone's mind or at least their emotion and in some cases they can even see the future.
We've already seen how the first two abilities can be used but with the others, being able to transfer life force can turn someone into an effective immortal since they can add to their own life by taking someone else's literal life. And with those who can read minds/feelings and see the future they can use this to basically predict any attack that's thrown at them and avoid it which basically turns them into Heimdall from God of War. They can even corrupt and control Spirits if they're powerful enough and are immune to Spirits altering their bodies and cannot be possessed by a Spirit
However, all these abilities, at least in the human world, have notable drawbacks.
As stated by the Lion Turtle that Aang met if you're own Spirit must be unbendable when trying to takeaway someone's else's bending or you risk being corrupted and destroyed. This likewise applies to Energy eating and transferring and both also leave them open to attack from anyone their not focused on. Doesn't matter how much life you drain or how unbendable your spirit is you're still human and a sword through the heart is still going to kill you.
And with the last group, just because you can read a person will not always be useful if they know how to clear their mind, not to mention the terrifying effect of needing to control how much you want to see in someone because you can loose yourself and can no longer tell if what you're thinking are your thoughts or the thoughts of those you are hearing. And finally just because you can see a punch coming doesn't mean you will be able to avoid it especially if your opponent is faster then you.
However, in the Spirit world, it's a different story as Spiritbenders can effectively become Gods. As we've seen the spirit world doesn't operate under the same rules as the human world does and we've seen someone who has a strong connection to the Spirits of Order and Chaos do imagine what someone who had the power to control spirits and the energy of life itself could do in there.
In the Spirit world Spiritbenders become effective reality warpers, able to bend space itself, make some become a child or grow old in an instant and literally bring down the sky itself if they so choose. This makes them more dangerous then any of the bender alive if they should ever go into the Spirit World Physically.
They are the most rare among benders because their own power could effectively cause them to die young since another draw back of energy transfer is they can give their own life to someone else so many Spiritbenders die young. The ones who live to adulthood are among the most dangerous people alive but also among the weakest because their powers require more dedication then even Firebenders.
This is to help explain why we've seen so few throughout the series and why the Avatar almost never uses it. Few are alive to teach the Avatar how to use it. Oh, and I would also have it where Aunt Wu from The Fortuneteller was a Spiritbender which is how she's able to see the future and people so well, or at least imply that.
But what about you, how would you go about including Energy/Spiritbending if you were writing for Avatar?
