Ahead lies...?

[Anastasia]

These looks to be something unique here - elementals in the shape of hounds, a mix of fire and earth like Magma. They're simply magma elementals in an unusual form and likely with some canine-esque powers, such as being good at pack hunting.

[Nephrite]

"...Well, we found some natives." Moore says. "You all stay up here -- just in case."

He begins to slowly descend down towards them!

[Anastasia]

The elementals show no reaction to you as you approach.

[Nephrite]

"Hello." Moore greets them in Ignan.

Something nice and simple will do the trick, hopefully.

[Anastasia]

A few of the elementals look up, one licking its chops and speaking, "Not of Fire or Earth?"

[Nephrite]

"I am not." Moore says. "I seek information." He says, this time in Terran.

[Anastasia]

Licking its chops again, "You want to know of Fire and Earth. Speak."

[Nephrite]

"Thank you." Moore says, switching back to Ignan. "I seek something known as  the 'lost house within.'"

Hopefully that may jog their memory or make them think of something.

Now that he thinks about it, the 'house' could refer not to a literal house, but to a family line or something...

[Anastasia]

The elemental speaks slowly, "Down. Secret and lost things are deepest."

[Nephrite]

Moore nods. "Thank you. Does this cave lead down?"

[Anastasia]

The hound looks to the side, a passage sloping down seen. "Down," It says.

[Nephrite]

"Thank you." Moore says, bowing his head. He raises a hand to the others to gesture them to follow him to the passage!

[Anastasia]

Done. As you go down, "They weren't bad for near hellhounds," Jetina observes, "I have only one question: How deep is deep here?"

[Nephrite]

"Probably very deep." Moore says. "Worst case, we can put some sort of marker down and plane shift back to it if we need to."

[Anastasia]

Gimme a d100 then.