The Heavenly Sin Divine Sword was first introduced when the Frozen Asgard Great Mistress met with Yun Che. It is said that this sword is from The king of eternal night( one of the 5 heavenly sect) and also the reason the sect got destroyed. (This is from chapter 300+ I think) At first I don't really care about that but on the Latest Chapter 680+. Spoiler: 680+ Warning! The Sun & Moon are scared at Yun Che now and they wanted YC to be invited to the Demon Sword Assembly. This assemble is about the sword showing or something because even if they got it for about 1000 years they can't still find what the secret of the sword is. So one of the reason for this assembly is to find someone who can open the secrets and the second reason is to show people that, the sword is not the reason they destroyed the 5th sect(forgot the name). This sword can make those who just entered Sovereign to have a battle power of half step to divine (Think, just how strong is that?) and considering YC is a MC and he also have jasmine, he can surely find the secrets of the sword but... So here's the thing.. Do you think YC will use it or let Hong'er eat it?