Harpy

Phantom Thief
5 years ago, a rich man received a card from someone. The person who sent the card called herself Thief Prom Queen, and forewarned that she will steal the precious painting that the rich man has been hiding. Although the man tried his best to protect his painting, The thief infiltrated the house with astonishing body movements and precision, taking away the painting like a breeze.

This was the first crime the thief had committed. The thief commited similar acts again the rich or big businesses thereafter, and although the Dai Li tried to arrest her with all the means they had, they failed and failed. However, this perfect thief eventually gets caught by its tail.

3 years ago, the thief infiltrated a research facility of Vultures to steal a remnant of a rare heirloom. However, due to her curiosity, she also ends up stealing the top secret document.

Vultures, enraged with her offense, orders their Disposal Squad to trace and hunt down this thief. Although the thief was able to shake off her prey with her air bending, she wasn't able to shake off the Disposal Squad, who used any means possible to hunt her down.

When Prom Queen was caught, she thought that Vultures would hand her over to the Avatar, the Earth King, or the republic police. However, Vultures decided that Harpy, who had read their secrets from the document, will be instead forcibly placed in a disposal squad instead of handing her over.

A team where Siyoung, a militia-strict commander was the Inspector. Siyoung thoroughly brainwashed the thief, and the thief was reborn as the shadow of Siyoung. 3 Years later, the thief now going by her real name, Harpy receive intense training and begun to take up the learning of Soundbending. One night, Harpy woke within the spirit world then suddenly pulled back into her body. Harpy screamed like it was a nightmare then she had remembered. She remembered everything, who she was, her past, she was no longer brainwashed. Harpy using her air bending skills to easily sneak out the facility with a little extra items with her. One year later still under the Vultures' radar, Harpy refuge to Republic City and enlisted into an underground fight club to keep her skills and body up to date, and she enjoyed a good fight.

Air Bending
Since Harpy have been trained by numerous of air bending masters in the Vultures and developing her own air bending techniques. Harpy demostrated that she is capable of creating large air currents capable of knocking people off balance, as well as increasing her agility to evade attacks, enabling her to take on multiple benders at a time. She could even defeat a master earth bender, while fending off Dai Li agents. Although she is not as powerful as a full-fledged master like Tenzin, she was proficient enough in combat to more or less hold her own against the more experienced airbender. She is also capable of using platinum trading-cards provided by the Vultures, both in close, mid, and long-range combat. She can take on multiple opponents at once and, since she is not a pacifist like most airbenders, she also uses her airbending in a more offensive and even lethal manner.

Sound Bending
By using circular movements, Harpy can build up massive inertia; this buildup of energy is released as a massive, overwhelming power. It also allows for counterattacks that blast opponents away, mimicking the explosive power of sound waves. Attacks vary from simple noises to shock-waves. Even a simple movement can create an noise, and Harpy can increase the power of her moves by using the momentum of her movement to simulate louder and more powerful sounds. This is also demonstrated with her use of platinum trading-cards to increase or create precision within the sound waves. Since sound can affect almost all physical objects, it can also be used to enforce the momentum of thrown objects or manipulate other objects (though requiring a higher degree of precision). Accompany to Harpy's incredible thief skills, Harpy is able to sense vibrations through the air, "seeing" by sensing her surroundings and making a mental image of it. It allows for 360 degree "vision", outside of normal line-of-sight. During her training, Harpy developed this ability; she is the only known human to use this technique. This allows Harpy to keep her hair as an airbender, due to most air benders shaving their heads to feels the breeze of incoming attacks. Harpy's recently invented technique is dampening sound. She can mask any sounds she make which allow them to sneak up on opponents, or make private conversations in a consolidated area. Also she can dampen the sounds of others so an enemy is unable to alert others of their presence.
 * Sonar Sense
 * Sound Dampening