To Save Them All

The fourth shinobi war has ended, but Naruto is the only one left alive. The war had caused them too much loss. What happens when Namikaze Uzumaki Naruto is stricken by grief and will do what ever it takes to take back what he lost? The answer? Go back in time. (A.N. There will be no pairings, just SakuNaruShika broma...