History of the Umars location (Iron Hammer Mine)

Clue

"As the sons and descendants of Arcturus, we Umars are the only race that has been gifted the blessing of creation by God. However... We never expected that our arrogance and self-righteousness would bring about such a catastrophe. This is the story of Demon Sword Velcruze... The worst thing ever created by our hands." (A related piece of information can be found in the Hall of Promise)

Story

"Umars took up all kinds of jobs to fund the construction of the Great Castle. One of those jobs was an order from a Demon to craft a demonic sword that would eventually bear the name Velcruze. The sword was sealed away after producing countless victims, but I fear the Umar and the folly that created the sword in the first place can never be truly sealed away. The blessings bestowed upon us by the God of Earth are truly precious, but sometimes I think along with the blessings came the curse that makes us crave forbidden powers."