This is mostly a Treasure floor, divided into two sections. The northeast section has a cell with one chest. The cell is locked, but there is a spot on the west wall that you can walk through. It contains the Sleep Blade, but is guarded by a mix of armored Soldiers and Magicians, so be careful.
The other section of B1A is a path that splits off into four rooms. You'll find the Dark Bow in the westernmost room, the Thief's Gloves and the prisoners in the central rooms, and two Potions in the eastern room. Remember that once you free the princess, you can't leave the Dreadnought until it is destroyed.
The other section of B1A is a path that splits off into four rooms. You'll find the Dark Bow in the westernmost room, the Thief's Gloves and the prisoners in the central rooms, and two Potions in the eastern room. Remember that once you free the princess, you can't leave the Dreadnought until it is destroyed.