Perturabo - The Hammer of Olympia is the fourth novella in the The Primarchs series. The novella was released in limited edition hardback in July 2017, and a non-limited release later in 2017.
Born to a life of political conflict, Perturabo was always considered a child prodigy among the people of Olympia –- indeed, his philosophical and scientific works were beyond compare. But then, after his rediscovery by the Emperor and decades of thankless military campaigning on the Great Crusade, the Primarch begins to resent his Legion's place in the Imperium. When word reaches him of turmoil on his adoptive homeworld, he orders the Iron Warriors to abandon their campaign against the xenos Hrud and crush this emerging rebellion by any means necessary...
- Perturabo - The Hammer of Olympia by Guy Haley