From Storm in Heaven:

Kyoji is a troubled boy who found peace thanks to his sensei, Tate, and the teachings of kendo. But during a kendo competition, Kyoji sees his master transform into an Inca warrior with eyes full of wrath. The two of them awaken the souls of ancient warriors within them, and start down the road toward repeating the same series of events that occurred in their past lives.

Zelda no Densetsu - Skyward Sword is an One-shot based off of the popular Nintendo Wii game of the same name. It's a prequel that tells the sealing of the main villain of the game and Link's Childhood.

Hirasawa was the scientist in charge of a special lab specimen that was a fusion between dragon and human DNA, dubbed the "Archetype". But when he escapes the secret organization "Ilumine" which was employing him, taking the specimen and his daughter Koyomi with him as he goes into hiding, Ilumine vows to track him down and retrieve the Archetype.

T.J. is a professional "trapper" for Ilumine, and his job is to track down and destroy the monsters know as "Dicapay" that are wreaking havoc all over the world. The organization orders him to visit Hirasawa's island hideout and bring the specimen -- now a partially-matured Archetype named Kiya whose outward appearance is that of an adolescent boy -- back to them.