I Asked You to Practice Swordsmanship, and You Played the Role of a Sword Demon and Unleashed a Great Annihilation?

Travel to a world where everyone is highly skilled in martial arts, ferocious beasts are rampant, and martial arts are respected! Qin Zhan only has an F-level talented sword wielder, who is so weak that he has to resort to martial arts. Luckily, the cosplay system is loaded! "Congratulations to the host for obtaining the Darkin Sword Demon template!" Kill enemies with unlimited upgrades! Therefore, Qin Zhan, who holds the sword demon Aatrox, can only face hundreds of millions of ferocious beasts! Endlessly strong! Great destruction! Listen to the extinct, dead silence! I don't want to be your enemy, I want to be the enemy of the world! Witness! Be immortal! The time has come! The end of the world! Is coming! This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.