"No. We have not killed any of the fifteen other races we have taken for defensive study. It has not been necessary. Consider that small scavenger floating by your head, Captain-Doctor, that is feeding on your vomit. Five hundred million years ago its ancestors made the galaxy tremble. When they attacked us, we unleashed their own kind upon them. Of course, we altered our side, so that they were smarter, tougher, and, naturally, totally loyal to us. Our Nests were the only world they knew, and they fought with a valor and inventiveness we never could have matched...Should your race arrive to exploit us, we will naturally do the same."