I had a harder time finding the stairs to go down to the next floor because this dungeon is wider than the derivation dungeon, but I somehow managed to get down to the 5th floor in one day. I arrived in the safety zone just before the large room in the deepest part of the 5th floor which is where the boss awaits.
After having the dungeon monsters as a midnight snack, I decided to challenge the boss tomorrow morning.
In order to fight it tomorrow morning, I went to sleep early to get enough rest.
Because I took the Skeleton Centipede out from my item box, I was able to get a good night's sleep in the chilly cave.