Fleet of Worlds) confronts a Pak Protector war fleet. The trailing edge of that Pak fleet, carrying the primary Pak Library, also figures prominently in Betrayer of Worlds, by the same authors. See also Protector Ringworld The Ringworld Engineers The Ringworld Throne Ringworld's Children Man-Kzin Wars XI Destroyer of Worlds Betrayer of Worlds References External links Larry Niven Known Space site Known Space Thought experiments Fictional extraterrestrial life forms