Violators

"It's been three days since I've entered the ruin but it still never ceases to surprise me," Olivia commented while watching a whole world inside a proficient grade ruin.

That's why there's a distinct rank between basic, below intermediate, and intermediate to proficient grade ruins. Even the frenzy maze, which has been ranked as an intermediate-grade ruin can't top this off.

At this ruin, everything felt real. One can feel that it has a unique sense of it without telling everyone about it. 

Currently, through the files and knowledge I know of, the Fordent Kingdom has two proficient-grade dungeons. One, the thing I knew of since it was mentioned in the novel, The Great River Of Haku, which appeared a century ago, and the other was Bridge To End which appeared fifty years ago.

Adding to Eve and the other one I knew, Fordent currently has four proficient-grade ruins.