Light of Arad: Forerunner

I was summoned to undo the corruption in Arad…? Jinsung is a user who has dedicated his life to Dungeon & Fighter. He was summoned by the Transcendent, Nemyr, to act as her forging tong.
[You shall become my forging tong to guide the blade through its trials.]
"I'll become a fire tong or whatever. I'm going to survive in Arad no matter what!"
Will Jinsung, a veteran player of Dungeon & Fighter, be able to fulfill his given duties and return to his reality?
Thus begins the story of the dark knight Jinsung to stop the end of Arad!