reincarnation of the devil hunter

Karz was the strongest and the most cunning of tte humans.He fought with the remaining survivors in a already lost war and died but some how woke up in a strange world in another body. He didn't understood anything but knew something gave him another chance to fight that being again and this time with preparation. So, in this new world of fantasy and kingdoms he will prepare and when that being with his demon army invade, he will be ready and anhilate them all as he himself was once at the hands of them