Book excerpt: The much-awaited sequel to "Sammy Tsunami and the Shadow Arrow" is finally here! Sammy Tsunami Is tall, thin and twelve with a touch of the weird and the strange. His life near the end of the sixth grade has settled back into what passes for normal. That is, until a mysterious stranger blows into town and threatens to unleash the World Cleaver What this awful sounding mystery is exactly, nobody knows. But vague clues lie in the dream country of Strangea, which Sammy visits in his sleep. Only that, he isn't really dreaming it up. Especially the part where a runaway comet is on a dangerous collision course to end all that is.