You finally chose to take the tunnel right next to the middle one. Literally and figuratively. It was to its right. How convenient.
What wasn't convenient was the darkness of the cave tunnel. It seemed unnatural, and seemed to press down on you.
You make a sound as you trip, losing your balance and falling. That's gonna hurt later.
You notice that the tunnel seems to have opened up a little. You look over the edge and see what looks like a DEEP ravine. Some weird creatures crawled around down there.
You watched your step, slowly making your way further. You didn't want to go falling down that ravine.
You turned a corner and found yourself in a little nook. You let out a breath of relief, now you can get some rest. You are about to sit down, before you spy some kind of crystal. You look at it, and can't seem to look away.
