Naruto: The Lone Wolf of the Leaf

At age 6 Ryu Namikaze graduates from the academy and becomes a Genin but after a mission that was supposed to be a C-rank mission all of his squad was killed except for himself. He was kidnapped and went through rigorous training for 4 years until he escaped, but knew he had been let go purposely for some reason. After Returning to the village after 4 years the 3rd Hokage was shocked to see he was alive. Ryu explained to him that his squad was killed and he was captured by a white skinned person with snakelike eyes.