Jinwoo had closed another S-rank portal and had received a reward from the system, a dungeon key... He looked at the item's description, not being able to get much information from it...

'SS-rank dungeon key: The tomb of the one who was sealed...' That was the only description the item had, and it made Jinwoo curious. What could be in this dungeon? Maybe some important item...?

Jinwoo thought for a while as he walked through the city, stopping in front of the subway entrance. He then picked up the black key, taking it to the lock floating in the air.

'An SS-rank dungeon has just been unlocked. Do you wish to enter, player?' A message appeared in the air in front of him.