This thing all things devours:

Birds, beasts, trees, flowers;
Gnaws iron, bites steel;
Grinds hard stones to meal;
Slays king, ruins town,
And beats high mountain down.

I think the answer is wind...(air or whatever other term you want to use). All living things "devour" air since all would die without it (including trees and flowers). Also it causes (and the things in it ie: dust, particles, moisture) cause damage to iron and steel over time. Strong winds can kill and destroy especially in tornado form. Lastly it erodes mountains. It fits all criteria.
Water could also fit.

Posted by Amy on 2003-06-09 20:24:47