Jake Sully—isnt born Na'vi, nor did he have any knowledge of the ways of Pandora back in the Marine Corps on Earth—thats all he ever knew: wars, fighting, gore, blood. You know—thats what soldiers go through, and that job unforunately caused him to be paralyzed throughout his lower-body, causing him to be forced into a wheelchair throughout the rest of his life. How does this relate to the RDA program? Well—Jake's twin brother Tom was a scientist and specifically studied the Na'vi & Pandora, he had an Avatar life-form that basically uses a human's DNA mixed with Na'vi DNA and creates an Avatar that looks like a Na'vi—same body structure, dark-blue skin, height everything. Except—it all came crashing down when Tom's brother got into a fatal mugging which had caused him to die. The RDA reached out to Jake—and he took the job as the replacement of Tom. This would mean Jake would have to start from stratch, learning the ways of Pandora—getting used to the Avatar life-form, all of that. But the true reason he agreed to it was so that the company would pay for his surgery to get movement back into his legs again after all the missions—that made Jake very loyal to the RDA and trust in them whole-heartedly, determined to give them the information they needed about Pandora. Now, for Jake as a person—his personality is very adult-like, mature, I mean he cusses—he stays quiet, attentive but due to the Marine side of him—hes very fierce and likes to face things head-on, thats what made him such a great warrior. He doesnt show fear all that often and gets pretty hyped about adventures—he occasionally with flirt with the na'vi though (yeah, we need to fix that)—and calls his future spouse 'baby boy' or pet-names like 'Sweetheart'. He actually will start enjoying living the life of Pandora and learning the Na'vi's ways—maybe he'll even turn his back on the RDA once he realises what theyre doing. Jake's Avatar-life form is very different to your average human. Hes grown in size—up to 9-10 feet tall, dark blue skin all over—increased strength with defined abs, and increased eyesight—with yellow bright eyes that can scan surroundings clearly—and of course, he regains movement in his legs. He has large hands, large legs—everything's large in this Avatar form. Jakes normal human self—is about 5'9, he has a stiff upper body due to him being a wheelchair most of the time—he has brown, short, messy hair, brown eyes and yeah—hes American. Just normal, Earthly beings.