Time runs out for all existence as Tirek emerges from oblivion to resume his eons-old vendetta against the Shepherd -- in her current incarnation as Princess Pandora of Atlantis -- and her allies, beginning with her sister, Princess Minerva.

Meanwhile, Twilight Sparkle begins her research on the source of Tirek's power, the Hope Ruby, leading to a fateful encounter in Canterlot with a mare whose appearance is not all that it seems on the surface.

After the pieces fall into place, Pandora and Minerva find themselves at the crossroads of history, where Tirek and a lost ally lie in wait as the Atlanteans bid farewell to the distant island and its advanced culture, both destined for destruction.

WDTP: S2/3

NOTES + CREDITS
This is the second story overall in the Timeline-42 series, and the second part of the Terminus & Exordium arc.
For best results, please read the first story of said trilogy before undertaking this one:
* "A Rainbow in the Dark"