is the 27th novel in the Horus Heresy series by Dan Abnett . It is a pivotal entry that consolidates numerous plot threads and focuses on the creation of Imperium Secundus . Core Premise & Plot
: The novel is famous for featuring a record number of Primarchs—five in total: Roboute Guilliman , Lion El'Jonson , Sanguinius , Vulkan , and the antagonist Konrad Curze . The Unremembered Empire
Believing that Terra has fallen and the Emperor is dead after the light of the Astronomican vanished, Primarch founds a "backup" empire in Ultramar known as Imperium Secundus . He intends this to preserve humanity's future, though the act itself borders on treachery if the Emperor still lives. Key Highlights is the 27th novel in the Horus Heresy series by Dan Abnett
: The introduction of the Pharos device on Sotha, which plays a major role in later lore, begins here. Believing that Terra has fallen and the Emperor