This is a theme that has fascinated the author throughout his career and even appears in his seminal work Ringworld, where the central character celebrates his birthday by instantly teleporting himself to different time zones, extending his “birthday.” The author also discusses the impact of such instantaneous transportation in his essay, “Exercise in Speculation: The Theory and Practice of Teleportation.”

The Carryx—part empire, part hive—has waged wars of conquest for centuries, destroying or enslaving species across the galaxy in its conflict with an ancient and deathless enemy. When they descend on the isolated world of Anjiin, the human population is abased, slaughtered, and put in chains. The best and brightest are abducted, taken to the Carryx world-palace to join prisoners from a thousand other species. Dafyd Alkhor, assistant to a prestigious scientist, is captured along with his team.

Moth was a beautiful planet, the only one with wings - two great golden clouds suspended in space around it. Here was a wide-open world for any venture a man might scheme. The planet attracted unwary travelers, hardened space-sailors, and merchant buccaneers - a teeming, constantly shifting horde that provided a comfortable income for certain quick-witted fellows like Flinx and his pet flying snake Pip.

Nothing quite prepared telepath Larry Greenberg for mind-to-mind contact with an alien. In the interest of science, Larry tapped the mind of Kzanol - and that was his first mistake. Kzanol was a thrint from a distant galaxy. He had been trapped on Earth in a time-stasis field for two billion years. Now he was on the loose, and Larry knew everything he was thinking. Thrints lived to plunder and enslave lesser planets - and what the planet Kzanol had in mind was Earth!

Nominated for both the Hugo Award and the Nebula Award, this short story introduces the Warlock, who discovers to his horror that the world's mana, the fuel that makes magic work, is rapidly dwindling. The news spells doom for magic-based society. Unfortunately, no secret that powerful can stay hidden for long.