The first floor of the Cavern of Earth has one of the game’s greatest anomalies: the Hall of Giants. If you travel west from your starting location, you will soon come to a hall that runs north to south. In this hall, every step you take will be a battle against at least 1 Giant, and possible an Iguana or two. This is a great location to earn both experience and gold, but be careful. A Giant can routinely damage your characters for 40 to 60 HP a hit.
I don’t recommend walking the hall from one end to the other, but rather walking back and forth in the entrance so that you can escape easily should things go wrong. I personally spend a little bit of time leveling here, but it is not necessary. You should be able to do fine at your current level.
There are several treasure chests on floor B1, none of them incredibly valuable. As always, please refer to the maps for item locations and the correct path. When you have finished your business on the first floor, it’s time to enter the maze.