On his pursue of Julius' airship, Sumo comes across the Dwarf Cave. The dwarf mentions that the airship went further into the west, stating that the Gaia Pass leads to the western lands. Another Dwarf mentions that he used to play in the Old Mine with Watts, he also tells him that if he wants to use the trolleys, oil will be needed which can be purchase at the store to the south. Watts likes the mines, and he went there today again. He's looking for some silver.

Sumo return to the Dwarf Cave after venturing through the mine, and finds out the Watts has finish making items out of the silver they found. He'll sell them to him and mentions that he'll be able to pass through Gaia when he's equipped with these.

Spoilers end here.