Dragon Fault is an Emperor Profound level heavy sword used by Yun Che. It has the soul of a young dragon within it. He got it after disarming it from the Stone Dragon General during the Dragon God Trial of the Primordial Azure Dragon. 
It was previously a Sky Profound level weapon but because the Azure Dragon used Yun Che's Emperor Profound dragon core, from the Fire attribute Emperor Profound Dragon that Jasmine killed, turning it into the first Emperor Profound weapon in the Blue Wind Empire.
After rescuing Hong'er Yun Che took out the broken Dragon Fault, saying that he would repair it when he reached the new world, but before he could Hong'er grabbed a broke part of Dragon Fault and ate it. 
The rest was eventually fed to Hong'er so Yun Che could get her to comply with him. 
- Has a baby dragons soul within it
- Weighed about fourteen thousand kilograms (30,864 pounds)
- Originally a Sky Profound Weapon; Upgraded to Emperor Profound Weapon by the Primordial Azure Dragon
- Someone from Heavenly Sword Villa
- In the original setting, Dragon Fault should have been broken by Ye Xinghan when he used the Sun Moon Calamity. But during the chapter, when Ye Xinghan forced the two of them in desperate straits, the author ended up forgetting. So, he broke it later.