Update 44 added the "Tracker of Temporal Tomes" achievement, which has the player recover 5 "Elusive Manuscript" lorebooks, each of which is a written account of some alternate reality in which some major event changed history divergent to the Tamriel we know.

For instance, there's the Traitor's Vault Temporal Tome, which describes a reality in which the player failed to defeat Molag Bal and Mannimarco succeeded in his plot to become a Daedric Prince. The Coral Aerie Temporal Tome describes a reality in which the Ascendant Lord succeeds and becomes the ruler of all of Tamriel.

I initially overlooked this achievement because I wasn't initially interested in the Undo, Lilac Purple skill style, but I decided to complete the achievement today and I'm fascinated by the lore presented by this achievement. I'd like to see another Temporal Tome fragment hunt, because I loved reading the "what if" stories and I'd love to read more!