which four elements are those?
Air, water, earth and fire
Bending the elements
As the Avatar, Aang is capable of bending all four elements (air, water, earth and fire). 
is avatar aang in the legend of korra Yes. Voiced by D.B. Sweeney what exactly is this avatar? It is a fictional character and the protagonist of Nickelodeon's animated television series what is the personality like? He is a vegetarian, reluctant to fight and kill does he have any power? Yes. He can  easily overcome any opponent that tries to fight him. He can also use all 4 elements at the same time.
Water, earth, fire and air. Water, earth, fire, and air Earth, water, air, fire, and (later) aether.
Aang Aang Classical element
Introduction Introduction Introduction
, Aang controls all four elements (water, earth, fire, and air)  water, earth, fire, and air Classical elements typically refer to the concepts of earth, water, air, fire, and (later) aether,
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Aang [SEP] Bending the elements
As the Avatar, Aang is capable of bending all four elements (air, water, earth and fire). The series' creators consulted a professional martial artist in the design of the show's fighting style; each of these styles' philosophies and set movements corresponds to a specific "bending arts". The creators made bending a natural extension of consistent limitations and rules of the world. Everything in Avatar's world, whether it be clothing, culture or infrastructure, is influenced by bending. The City of Omashu uses a complex system of gravity and earthbending to transport supplies. The Water Tribes were a naval superpower: their buildings are made of ice and used waterbending as mechanisms for their walls and gates.