World Fraction (Episode)

World Fraction (ワールドフラクション) is the 14th episode of the Log Horizon anime. It aired on January 4th, 2014.

Synopsis
Shiroe and Akatsuki follow Ri Gan to his library, where he had shelves filled with books and scrolls.

Being an academic in the study of World-class magic, Regan offers Shiroe and Akatsuki an explanation of the World Fraction spell and its thrice use in the world's history, with Shiroe correctly deducing the third time being the Apocalypse. Regan explains that 350 years ago the Human, Elf and Dwarf races destroyed the Alv kingdom out of technological jealousy. Seeking revenge, the remaining Alves cast the first World Fraction which resulted in the creation of the endlessly respawning demi-humans which pushed the planet into a world war. This caused humanity to create powerful hybrid races to aid in the war, until they were forced to cast the second World Fraction which summoned the Adventurers to their aid, some 240 years ago. As Regan also explains that Shiroe's name appeared in the world's history some 98 years ago, Shiroe confirms the events using the game's rate of time as it correlates to the real world, including the start of the open beta which brought the human-controlled Adventurers and when he began playing Elder Tale. Regan then moves on to explain his Spirit Theory which involves how revival works and that memories in the form of XP are lost during the process—a theory which Shiroe decides to withhold from the Round Table for the time being. Meanwhile, Minori finally decides to speak her mind to the training group.