Mechanicum

Great look at Mars at the start of the Heresy

In Mechanicum, Graham McNeill turns his considerable talents toward one of Warhammer 40,000’s most enigmatic factions: the shadowy priesthood of Mars. On paper, the novel promises a rare and tantalizing premise, a glimpse behind the curtain of the pre-Heresy Mechanicum, that blend of techno-religious zealots and cybernetic artisans who power the Imperium’s engines of war. But while the gears grind and the war engines roar, the human, or post-human, core of the Mechanicum remains frustratingly out of focus.

We are, it’s true, offered a few fleeting insights into the inner workings of Martian society before the cataclysmic schism of the Horus Heresy. But these moments are superficial, often sidelined in favor of grand set pieces and escalating conflict. The finer details of culture, belief, and daily life are treated more like set dressing than the substance of the story.

And collapse it does. By the novel’s midpoint, the plot gives way to titanic warfare, with the story slipping into a blur of clashing god-machines and pyrotechnic spectacle. While some readers may come for the combat, others looking for a more textured exploration of identity, faith, and technological dogma may find themselves wanting.

There are hints (faint ones) that McNeill is planting seeds for future relevance within the wider Horus Heresy series. But unlike its stronger peers, Mechanicum feels oddly disconnected. Its events ripple outward with barely a splash, leaving readers to wonder if what they've just read will matter at all in the grander scope.

For diehard fans of the Knight Houses or devotees of Titan-scale warfare, the novel may offer a satisfying indulgence. But for those drawn in by the allure of the Martian priesthood’s mystery, its ancient rites, its cryptic doctrine, its uneasy coexistence with humanity, Mechanicum is a disappointment. Beneath the towering robots and scorched red sands, there was a richer, stranger story waiting to be told.

Horus Heresy Bolter or Bin Rating: Bin (Not really worth the time to read)