I believe this is my first comment on this site, but I have to. The idea is good. Could likely use some fleshing out, but others have already expressed some points of improvement and I don't want to be redundant. I just wanted to say that this was a very entertaining read. Also, the observation that the long-lived elf would spend more time in basic training was so obvious I wonder how I've never run across it as such. Bravo. Go to Comment
The PCs traveling along the road/path/trail begin to hear a low droning sound. As they approach they find their path obstructed by hundred of thousands of droning insects. Locusts swarm though the air, feasting on the grass and plants. Passage will be slowed, but the insects pose no threat to the party, aside from being crunchy and disgusting underfoot, climbing into pouches and eating exposed food goods.