Recurring catastrophic wars on Roshar in which the Fused (cognitive shadows of ancient Singers inhabited by Odium's Investiture) return to wage war against humanity. Each Desolation brought devastation that set civilisation back by centuries or millennia. The Heralds and the Knights Radiant fought against the Desolations for thousands of years. The current events of the Stormlight Archive represent a new Desolation after thousands of years of peace.