Plenty has been written about what happens at the start of a Pass on Pern, but how does the planet react to a change over from fighting Threadfall to the long Intervals during which the Weyrs are no longer needed to fight the voracious Thread? Set at the end of the fourth Pass. (Mostly canon.) (Updates sporatically))

"Time protects itself..." In the final story of the Dragonchoice trilogy, the riders and dragons of Madellon Weyr face their gravest challenges yet as Pern is rocked by events that will change the world forever - past, present, and future... Book three of the Dragonchoice trilogy.

In "The Dolfins of Pern", T'gellan is Leader of the Weyr at Landing; Mirrim is his mate. They were already measuring each other up in the original trilogy. How did a bronze rider end up with a green? And of all the green riders, it's that unpleasant piece of work, Mirrim. Here's what could have brought them together.