Kenja no Tsurugi

Because of an accident he had died and was reincarnated into another world. There he was reincarnated as a baby and was to start a new life. He then later learns that the world he had reincarnated to was the game that he had already played. Moreover, he was reincarnated into the character who was set to die early into the game’s opening scenario. In order to not follow the same fate of dying, he utilized all of his knowledge of the game to make himself stronger. Before long he was able to attain unparalleled strength and skills. He then marched forward unto the continent the Demon Lord had decided to conquer.