Hard Science Fiction, Science Fiction || For decades, the spacefaring species of Known Space have battled over the largest artifact—and grandest prize—in the galaxy: the all-but-limitless resources and technology of the Ringworld. But without warning the Ringworld has vanished, leaving behind three rival war fleets. Something must justify the blood and treasure spent. If the fallen civilization of the Ringworld can no longer be despoiled of its secrets, the Puppeteers will be forced to surrender theirs.