Complex sentence: Story arcs can live through several years of play, the current year on the Living Greyhawk Calendar, measured as years that have passed from the Twin Cataclysms, is 596 CY.
Split into simpler sentences: Story arcs can live through several years of play. The current year on the Living Greyhawk Calendar, measured as years that have passed from the Twin Cataclysms, is 596 CY.