Storyline
The novel Time Spiral, written by Scott McGough, tells the story of Teferi's return to Dominaria. It expands the setting and events depicted on the cards of Time Spiral into a full story. Teferi returns to Dominaria three hundred years after the Phyrexian invasion, to prepare for the return of Shiv and Zhalfir, the lands he phased out during the Phyrexian invasion. The stress of constant warfare and apocalypse (the Brothers' War, the Phyrexian invasion, Karona's War), combined with mana-draining rifts created by the overlaying of Rath and Skyshroud (among other events across the multiverse, such as the near-destruction of Ulgrotha), have set off a chain reaction that has created ripples in the temporal fabric of the planes. The unphasing of Shiv threatens to destroy the plane of Dominaria, and in turn the entire multiverse.
After the defeat of Karona, the rifts in the planar fabric began to act as mana sinks, draining the lands of mana. Life on the plane became harsh and the temporal rifts caused people and objects from Dominaria's past to be "dropped" into the present, leaving people stranded in unrecognizable lands that are thousands of years from their time.
Read more about this topic: Time Spiral