In the middle period of the Great Nirvana Period, the great human scientist Kelo Desenna invented an alloy harder than diamond—the Kelo Alloy—using materials from monster corpses and the "Blue Gold" metal discovered on the moon!
Human powerhouses no longer had to fight monsters with their bare hands. They now possessed terrifying weapons capable of cleaving through monster scales and fur.
This was a major historical event, a turning point in the war between humanity and the monster race.
Previously, when humans fought monsters, either the human armies unleashed their full firepower and physically destroyed their opponents, or human powerhouses had to be a minor level stronger than the monsters and crush them with overwhelming strength. Only a very small number of people possessed weapons obtained from the Ancient Civilization Ruins that allowed them to fight monsters of the same level, or even cross a minor level, precisely because they could breach the monsters' defenses.
However, there were far too few weapons obtained from the Ancient Civilization Ruins, while the monsters numbered in the hundreds of billions.
All of humanity was at an extreme disadvantage. It seemed that humans were about to lose their position as Earth's foremost overlords.
But with the appearance of the Kelo Alloy, humanity finally gained hope. After all, they now had something capable of breaching the monsters' defenses.
After the Kelo Alloy appeared, the Warrior Level and War General Level martial artists finally rose to prominence. Having fought monsters for so long, they naturally knew where the monsters' weaknesses lay.
Once they had suitable weapons, their monster-killing speed rose rapidly.
On the battlefield, they assisted the army and finally advanced from the sidelines to the level of coordinated combat.
In the past, it had made little difference whether they were present on the battlefield or