You get one elemental power, and one weakness. The weakness completely neutralizes your power, like how kryptonite removes Superman's powers. The elemental power is what you can do, like the Benders from Avatar.
Name: What are they called?
Age: How old are they?
Race: What race are they? (Human, elf, dwarf, ect)
Elemental power: What element do they control?
Elemental weakness: What neutralizes it?
Background: Where do they come from?