The green tide on the mountains collided with the black tide below. The Tyranids' black tide looked ferocious and terrifying, but the mountains held by the Greenskins stood firm like reefs.
The Swarm Consciousness had underestimated the Orks' fighting strength and tenacity here, but that was no great problem. Its preparations were more thorough: not only did it have more troops, it also had Lictors and a Norn Apostle ready to decapitate the Ork Warboss at any moment.
The meddling Chaos forces were nearby, but they seemed to be conducting some strange ritual. They had gathered vast quantities of skulls and blood, and had even sacrificed many of their own cultists.
The cultists' blood was used as paint to draw blasphemous patterns, covering every corner of the altar.
Based on past experience, the Swarm Consciousness judged that these Chaos Cultists would need at least eight days to complete their ritual. That would give it the perfect opportunity to crush the Orks and plunder their biomass.
Vorda's plan did indeed require eight days. The Blood God's sacred number was eight, so he had built an eight-story tower to serve as an altar. He had chosen eighty-eight cultists as sacrifices and soaked the entire altar in their blood.
Then, in the eight directions around the altar, he had erected eight skull mounds using the skulls of Orks and Chaos Cultists. Each mound contained eight hundred and eighty-eight skulls.
A candle made from corpse fat burned atop every skull. These candles would burn for eight days and eight nights, and the ritual would be complete when the last gleam of light faded on the final night.
A perfect ritual would draw more of the Blood God's attention and grant Vorda greater power.
That was the theory, at least. Vorda had done exactly this