Emperor-ranked weapon. Not only was it an emperor-ranked weapon, from the aura it radiated, it was a high-grade emperor-ranked weapon!
Di Tian, an initial-stage immortal emperor, could actually forge a high-grade emperor-ranked weapon.
Weaponsmithing was different from inscribing formations. Knowing formations was just the base of weaponsmithing. Weaponsmithing was much more complicated in comparison.
High-grade emperor-ranked weapons were able to boost a peak-stage immortal emperor's combat prowess. If an emperor had a weapon like that, their strength would explosively increase. From this, one could very well tell how valuable such weapons are. Although there were many emperors in the vast Lifire City, peak-stage emperors were still considered upper echelon characters.
From this, one could tell how highly sought after weaponsmiths were who can create high-grade emperor-rank weapons.