The Legend of Korra continues the story that first began in Avatar: The Last Airbender, taking place about 70 years after Aang defeated Fire Lord Ozai to end the Hundred-Year War at last. Legend of Korra uses the same bending-based combat system as Avatar, but with some new twists to bending and modern technology alike.
In Avatar Korra's time, machines and bending are equally powerful, and either or both of them can reshape the world in drastic ways. Modern benders must rethink how they use their talents to affect the world around them, and that includes pioneering all-new forms of bending. All four elements are open to experimentation, but arguably, earthbending has made the most progress to become the strongest element of all.
The Physical Power Of Earthbending In Korra's Era
Benders of all four elements have innovated new ways to manipulate their elements, such as Hama learning to bend people's blood and Zaheer relinquishing his attachments to gain true flight. Even the weakest element, fire, has the power of lightning bending at its disposal. By Korra's time, however, earthbending has taken a substantial lead.
To begin with, earth has the advantage of using solid materials in its bending, primarily dirt and stone. This allows earthbenders to form solid barriers on the defensive, hardened projectiles on the offensive, block landslides, form bridges, trap people or vehicles and more. Waterbenders can do that with ice, but ice is easily melted with fire, and water isn't as readily available as dirt and stone are. And in Korra's time, a few benders, including Ghazan and Bolin, could bend lava -- a devastating technique that no other element can match in destructive potential.
In Korra's time, the world is heavily industrialized, especially in the metropolis of Republic City and Suyin's all-metal city of Zaofu, and more earthbenders than ever can control impure metals. It appears that only a minority of earthbenders can bend metal, but that's still plenty of people -- far more than in Aang's time, when Toph Beifong was the sole metalbender. Metal is simply everywhere, from combat tanks and zeppelins to Satomobiles, bridges, train tracks, household appliances and soldier armor, and earthbenders can control it all.
It's a serious advantage when an earthbender can flip a speeding car over with a motion or tear down a metal bridge, and they can reshape or repair anything out of metal, such as barriers or improvised armor, as well. Modern technology has far more synergy with earthbending than the other elements, even counting lightning benders like Mako who can help build cars with their talents. This is how the tyrant Kuvira built her Earth Empire, complete with a giant robot operated entirely with bending. The other three elements don't have anything remotely like that.
The Subtle Arts Of Earthbending
Earthbending benefits greatly from the abundance of technology and stone in the modern era, but this element isn't always so blunt. In both Aang's and Korra's time, earthbending is capable of subtle techniques that the other elements cannot match, even the famously spiritual and refined art of airbending. It's mainly the Beifongs and their associates who demonstrate this.
Earthbenders can sense vibrations in the earth and even other people, and they can serve as living lie detectors, as Toph demonstrated in the original series. Being born blind but learning from the badger-moles directly, Toph maximized her earthbending and used it to "see," as her bending is more sensitive than anyone else's.
With that technique, Toph could sense changes in another person's blood pressure and heart rate and determine when they were lying -- since lying is stressful and causes physical changes in the person. Toph once did this to help Aang find Appa in Ba Sing Se, and two generations later, Suyin Beifong's ally Aiwei demonstrated his own expertise in lie detection. The only problem was that he was the actual traitor, so Suyin couldn't use him to find any other double agents operating in Zaofu.
Finally, Toph and her daughter Lin Beifong often used earthbending to sense vibrations in the ground and sense the terrain and people all around them, even deep underground. It's like a variation of sonar, allowing the bender to form a 3-D map in their head -- a feat no other bending art can do. Granted, a talented airbender might use their bending to sense objects based on moving air currents, but this won't help them underground, while an earthbender can sense anything so long as they have stone, dirt or metal in some form to work with. Toph once used this art to locate Fire Lord Ozai's underground bunker during the Fire Nation eclipse invasion, and Lin used it to form a mental map of the Equalist army's underground hideout to try and locate Korra.
