Editing Xenos of the Hektor Heresy (section)

===Ruavu Grun===
{{Main|Ruavu Grun}}

In the wake of the Rebellion which nearly destroyed the Imperium, it is hard to remember that halfway through the Great Crusade the Imperium was menaced by a different threat, one that emerged from the outer dark and swept through Segmentum Tempestus like an unstoppable wave, laying waste to vast swathes of the Imperium.

Once the name ‘Ruavu Grun’ symbolized a dark tide of destruction which threatened to reverse the entire tide of the Great Crusade, and which took great sacrifices from the Astartes and the Mechanicum to contain and eventually eradicate.