The Great Dying is a cataclysmic event that occured across all worlds in the Wonder Boy series and was responsible for the death of all dinosaurs and their passing into Ghost World. Dinosaurs had previously ruled all worlds as the dominant species, but were gradually wiped out during this period. Although the actual cause isn't specified, the symptoms that led to extinction include fierce winds and arid, barren ground. The Dinosaur King remains bitter about this and is keen to "reclaim their birthright".