The year is 26 CLE. The Black Mist has spread across Valoran, plunging its nations into a Harrowing seemingly without end. Only Demacia and Ionia have thus far shown the ability to drive it back: Demacia by calling on holy magic to banish the ghosts back to the realm of the dead, and Ionia by summoning the spirits of honored ancestors to mediate with the harrowed souls and restore balance. Having tried and failed on their own, the League’s quarreling member-states have at last agreed to band together in a joint effort. As the Demacian approach of banishing the spirits and the Ionian approach of summoning more spirits to Runeterra are antithetical to one another, the decision has come to the League of Legends, final arbiter among nations. A contest of arms upon the Fields of Justice will determine the victor.
As of 28 November, 26 CLE, Arc IX: Black Winter has begun.