Trilobite is an educational game repeating a half billion years of marine evolution. One to three players design an animal genotype set in the ocean of 500million years ago. Another player known as the “Mariner,” controls the trilobites, ammonites, plesiosaurs and other animals indigenous to the era. The genotypes must survive the great radiation of life called the Cambrian explosion, as well as the Permian mass extinctions, and the Cretaceous event that exterminated the dinosaurs. The genotypes evolve and metamorphose as they eat the marine animals they encounter. —description from the publisher