I'm a Sword Saint. It's Normal to Kill Through the Devil's Cave, Right?

Cool article + single female protagonist + no system + invincible flow + dual sword flow In 1773 AD, a purple gas of unknown origin appeared all over the world. Once humans enter, they will become irrational demons. In 1800 AD, humans discovered that some ugly monsters began to appear in the purple gas. In 1805 AD, scientists named the purple gas "Purple Haze" In 1850 AD, World of Warcraft aggressively attacked surrounding countries and cities, and human civilization was in danger. In 1855 AD, scientists discovered that human beings could use the energy and blood in their bodies to practice martial arts, which ushered in the era of martial arts for all.