"You've solved the riddle, Horay! Woohoo! But you don't think it's this easy, do you?" says the raspy voice. You are hit with a feeling of relief, for about five seconds, as you realize that you're still in the labyrinth, just this time it's a room with four pedestals. One has a lit torch, one has a glass of water, one has a small sprout of grass, and one has a rock garden with sand. You look around, and realize that there is sand coming in from the cracks in the walls. If you don't get out soon, you'll be buried alive! You sprint for the door, but realize it is locked, with a pedestal attached to it. You are about to turn away, when you see words on the pedestal-
I'm here again, to get you through,
some call me the Wrlä, but is it true?
Without legs I swiftly run,
A roaring fall without a tongue.
The cause of many deaths am I,
And yet without me, all would die.
You realize that the answer to the riddle is