Given that she's not led you wrong thus far, you follow the path into the darker tunnel. It grows very narrow within a few yards and stops at a stone face. You start to turn around when the girl reaches and pushes against the stone. To your surprise, it budges a little. You push as well and the stone moves aside rather effortlessly. It's only meant to look impassable.
Inside is what looks like an armory. There are rows of spears with sharp, stone blades. There is a seam of hard quartz, and the room is very warm. You suspect a lava flow or hot spring is nearby. But, what astonishes you the most are the cave drawings.
The images depict an exodus from the surface. You see stick figures of people living among trees and the sun is shining. Then the sun goes away, the trees die, and everything is encased in cubes that you guess are ice. The people find a tunnel underground and live there, but then they start to fight the lizards. The last drawing shows the people with spears in an all out brawl with dozens of smaller lizards, and one really big one. You wonder if the one you saw is a descendant of that original lizard.
The girl taps on your shoulder and brings you back to the present moment, and points to her ankle. You apologize and let her down gently. Then, using what's left in your first aid kit you tend to the sprained ankle. You know enough first aid to wrap it tightly in gauze tape and apply a little painkiller to the surface of the skin. When you're done, she stands up and tests her weight. With the help of a spear handle to lean on, she's able to move around pretty freely. Soon, she doesn't even need that. For the first time since you've met this girl, she smiles at you.
For the next few minutes, she tends to gathering up several supplies. The moss, in addition to providing light and clothing, can be used to make rope, as well as food. She munches on a piece and offers some to you. You decline and pull out a protein bar from your pack. You offer her a piece, but she spits it out after a moment, preferring the flavor of moss.
After gathering a sufficient amount of supplies, and stowing it in your pack without asking, the two of you leave the armory and head back down a different tunnel. This girl has a purpose. Not simply to escape, but something more. Your curiosity compels you to follow her. Up a different tunnel that soon becomes very steep. The two of you climb, and soon find yourselves traveling up a seam with a large crack in the bottom, revealing a massive chamber below, full of the lizards. There is heat in this chamber, and nearly all of them are basking on the hot rocks, soaking it in. At one corner, just below the two of you, are about six men with the same pale complexion who appear to be captured. One lizard lays in front of them, with one eye open, and one eye closed. The girl turns around and pulls the rope from your pack. There is a heavy knot tied at one end that fits neatly and snugly into a groove cut in the rock, then lets the rest drop down. The end dangles just a few feet over the partially asleep lizard. The men see it, but do not act right away.
The girl gestures for you to hold the knot in place, and make sure it does not slide out. You realize she intends to climb down, but you wonder about her ankle.