I checked the number of cyclops; the maximum is 999,999, and it doesn't increase beyond that. Once, I approached them and managed to kill 1200 (I had a small army), then I returned to the saved game, checked all the neutral creatures, and they all had the same number. It seems they are capped at one million. Over several months, their numbers haven't changed, so I want to try to eliminate them with a large force. I'll spend a couple of weeks at the computer, and then we'll see. There's no rush, and it should be quite exciting.