An E Rank Dungeon wouldn't be that big since it was only an E Rank Dungeon.
The reason that dungeons that were higher ranked were bigger was because of the concentration of mana in those dungeons being higher.
With more mana in the dungeons, more of it was absorbed by the dungeon itself to make itself bigger.
For these lower ranked dungeons that didn't have as high of a mana concentration, it meant that there was far less mana for it to sustain itself. As such, it was also why this dungeon was much smaller than most of the higher ranked dungeons I had visited.
Since our job today was just to clear out this dungeon, it wasn't as if this was a bad thing.
The sooner that we found the boss and cleared the dungeon, the better.
After all, we were just doing this to make sure that this dungeon didn't experience a dungeon break.
