Good eyes, I never noticed anything like that. I can think of a few explanations:
1. It's an enemy units and the advisor is saying, "keep your eyey on them, sir."
2. It's a joke. They did say that they wanted to bring back the lighthearted humor from the first game.
3. It's a wandering band of some kind
4. Maybe a wandering resource? (I doubt it, but I'm just spewing ideas.)
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<FONT COLOR="blue">You move like I want to, and sing like your eyes do.</FONT c>