It seems as though Warhammer is well aware of fan discontent regarding a large number of units not included in the new Horus Heresy edition, because it just dropped a PSA addressing the issue.
After Horus Heresy Saturnine went up for pre-order and coverage embargos lifted, many in the community noticed that older units and loadouts that players had spent a significant amount of time converting weren’t anywhere to be found in the Liber army rulebooks. This caused a lot of understandable upset – so much so that Warhammer has had to drop a post explaining that the situation might not be as dire as it appears. That’s because “the upcoming Legacies of the Age of Darkness PDF is a huge document which will allow you to continue to use the vast majority of miniatures you’ve amassed over the last decade of collecting.”
Although it’s not due to launch until after Saturnine hits shelves at the end of July, Warhammer’s post rattles off an extensive list of units, vehicles, and characters that’ll get rules in the PDF. These will be tournament-legal at official Horus Heresy events (for third party events, it’ll apparently be down to the organizers).
According to the post, the reason these stats weren’t included within the Liber books is a matter of space and because they reflect the game’s current range of available miniatures.
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