- "The voice of Chaos."
- —Book's tag-line
Kryptos is the second short story published in the Horus Heresy that was not originally part of an anthology novel. It was first published online in 2012 and was later included in the Legacies of Betrayal anthology novel.
Bloodied but unbowed, the Raven Guard and the Iron Hands fight on. In the wake of the Dropsite Massacre, the Shattered Legions are still prepared to bring the fight to Warmaster Horus and his traitorous allies. On the doomed forge world of Cavor Sarta, two veteran warriors of the Imperium strike deep into the heart of Dark Mechanicum territory. With Bolter and blade ready to cut down any who cross their path, they will seek out the enemy's most valued asset: the mysterious Kryptos.
- Kryptos (Short Story) by Graham McNeill