A Single Thought Swings the Sword into a River

[No time travel + no system + no harem + no grandfather] The way of heaven has collapsed, the gates of heaven are closed, and the gates of hell are closed. The human race is surrounded by enemies and is in urgent need of heroes descending from the sky. Then it falls from the sky! Fate whispered to the boy: "You cannot withstand the storm." The young man replied: "I am the storm!" Flowers left in the world, lonely trees, containing the frost and smiling at the wind and clouds A wanderer, a wanderer in the mountains, going through hardships and carrying a sword to traverse the mountains and rivers