What exactly is the Yin Iron Sword? What's the role?

Yin Tie is an ancient thing, originally a complete piece, which can absorb evil spirits and is a very gloomy musical instrument. Xue Chonghai forged ordinary people into immortal puppets with yin iron in an attempt to dominate the world with this immortal army. His plot was shattered by four families. Silver and iron were torn apart in the shocking war, and were suppressed by Shi Lan, Dafanshan dancer, Hu Hua dancer and Yang Xue in Gusu.

Just as Wei Wuxian told Lan Zhan, Yin Hufu is not an iron shadow, but it was really forged by Wei Wuxian and Lan Zhan with that iron sword full of rage when they slaughtered Xuanwu. I spent four or five hundred years in the turtle shell corpse heap, and was influenced by the resentment of countless people who were swallowed up by the monster beast. Using this sword to refine Yin Khufu, you can summon thousands of Yin corpses for their use. In addition, Wei Wuxian was thrown into a mass grave by Wen Chao and others, and Yin will have greater power with the help of him.

Yin iron contains too much energy, which can be used to cultivate sophistry, and eventually become the purpose of driving away ten thousand pieces of corpses for their own use. But this kind of training is intolerable to many decent people, who think it is too opportunistic. So in the play, many people want Yin Tie, but they don't want to be known by others, so they all compete for Yin Tie in secret.

Chen Qing and Yin are two major musical instruments released by Wei Wuxian after he walked out of the mass grave. Chen Qing's appearance is a black flute, which can attack and defend rhythmically, similar to the Guqin of the Blue Family. Yin and the greater role is to manipulate evil spirits, which is particularly obvious in large-scale battles. It can manipulate the dead for their own use, so this is the biggest reason why people all over the world have been fighting for Yin He and Yin He won the world.

Wei Wuxian got the Yin Iron Sword, refined it into Yin Hufu, and then created his own cunning way. He can use Yin iron to summon spirits and exorcise evil spirits, and become another person who can control Yin iron after Wen Rehan. Later, Wei did not envy his physical death, and the yin and the tiger were destroyed. Therefore, "yin and yang are the best in the world" is just a rumor. On the contrary, many people died because of this yin iron.