Seismic sense

"earth"

- I see with earthbending. It's kind of like seeing with my feet. I feel the vibrations in the earth, and I can see where everything is. You, that tree, even those ants.



Seismic sense is a sub-skill of earthbending that constitutes for physical sense. Through learning this skill, earthbenders can detect vibrations in the ground to perceive objects, people, and other aspects of their environment, essentially acting as sonar but through the ground.

History
The badgermoles, the original earthbenders, were the first users of seismic sense. Naturally blind, the badgermoles used their ability to navigate their world. It especially helped them navigate the ever-changing tunnel network of the Cave of Two Lovers.

The first known human practitioner of this technique was Toph Beifong. Born blind, she developed the sense at a young age by learning from the badgermoles. Toph used the ability to develop a form of earthbending different from the normal technique. Along with this, she used seismic sense to discover the abilities of lie detection and metalbending.



The second known human practitioner of seismic sense is Aang. Taught by Toph, Aang was fully capable of using the sense to perceive things and movement out of his line of vision or while blindfolded.

Sometime after the Hundred Year War, Toph's daughter, Lin Beifong, also learned seismic sense. She used the ability to discover a factory operating underneath the Sato mansion, where Hiroshi Sato was manufacturing technology for the Equalists.

Use
First and foremost of seismic sense's applications is the ability to perceive surroundings. By sensing vibrations in the ground, earthbenders can perceive their surroundings as precisely as normal sight. Practitioners can use the sense to detect things out of their line of sight, even right behind them. Obstacles that would normally obstruct regular vision, such as walls and thick dust clouds, are ineffective against seismic sense. Caverns and other cavities deep underground can also be detected by an acute use of seismic sense, as well as minute bodies, sometimes imperceptible even to the normal sight. Even earth that is not on the ground can be detected.

Metalbending


Notably, seismic sense also allows earthbenders to bend metal. Earthbenders who do not possess seismic sense cannot do so, but not for lack of potential. Minute amounts of earth still exist in metal, but are so small and elusive that normal earthbenders cannot "grab" them. Seismic sense users, however, can detect the small amounts of earth still present in the metal, enabling them to bend it.

Lie detection
Another ability enabled by seismic sense is lie detection; the sense allows earthbenders to sense the interiors of humans, and any changes in their physical status, such as a change in heart rate. Since humans have a physical reaction when they lie, earthbenders who use seismic sense can tell when it occurs. However, the reaction can be suppressed by skilled liars, making earthbenders unable to tell if the statement is a lie.

Limitations
Seismic sense is not without its limitations. Seismic sense only detects things in contact with the ground; objects floating in water or thrown in the air are undetectable unless they are earth. The practitioner must also be in contact with solid ground to use the sense at all; again, if the user is in the air or water, or even standing on a non-earth solid such as ice, the bender will be unable to sense anything.

Sand, although an earth-based substance, is not firm like normal earth, and renders seismic sense "fuzzy" and very imprecise. Uninterrupted contact with the ground is preferred for the user - an object such as a shoe sole interferes with the sense. The sense also has considerably less range than uninterrupted sight, and it does not allow for perception of facial features or written characters.

Known Users

 * Badgermoles
 * Toph Beifong
 * Aang
 * Lin Beifong