There were not many of the goats. Each year the winters were longer, requiring the stocking of a larger supply of hay. The time would come when the summers would be so short and the winters so long that they could not keep goats at all. And by then, when Big Winter had closed in on them, the summer seasons would be too short for the growing of the orange corn. They would have nothing left but the hunting. They had, he knew, reached and passed the zenith of the development of their environment. From a low of forty-nine men, women and children in dark caves they had risen to a town of six thousand. For a few years they had had a way of life that was almost a civilization but the inevitable decline was already under way. The years of frozen sterility of Big Winter were coming and no amount of determination or ingenuity could alter them. Six thousand would have to live by hunting--and one hundred, in the first Big Winter, had found barely enough game. They would have to migrate in one of two different ways: they could go to the south as nomad hunters--or they could go to other, fairer, worlds in ships they took from the Gerns. The choice was very easy to make and they were almost ready. In the workshop at the farther edge of town the hyperspace transmitter was nearing completion. The little smelter was waiting to receive the lathe and other iron and steel and turn them into the castings for the generator. Their weapons were ready, the mockers were trained, the prowlers were waiting. And in the massive corral beyond town forty half-tame unicorns trampled the ground and hated the world, wanting to kill something. They had learned to be afraid of Ragnarok men but they would not be afraid to kill Gerns.... The children with the goats reached the stockade and two of the prowlers, Fenrir and Sigyn, turned to see him standing on the wall. He made a little motion with his hand and they came running, to leap up beside him on the ten-foot-high wall. "So you've been checking up on how well the young ones guard the children?" he asked. Sigyn lolled out her tongue and her white teeth grinned at him in answer. Fenrir, always the grimmer of the two, made a sound in his throat in reply. Prowlers developed something like a telepathic rapport with their masters and could sense their thoughts and understand relatively complex instructions. Their intelligence was greater, and of a far more mature order, than that of the little mockers but their vocal cords were not capable of making the sounds necessary for speech. He rested his hands on their shoulders, where their ebony fur was frosted with gray. Age had not yet affected their quick, flowing movement but they were getting old--they were only a few weeks short of his own age. He could not remember when they had not been with him....