In Nskanetis, ice is an omen of death. Not Death - that being is associated with the leyline, and Nskanetis herself. Ice and death is an ill omen, something inherently Wrong on a world of warm climates. Like a fever, like a thunderhead, it is a warning - something is coming.
When the Hive King's ship moored in Octairia, coated in ice that stretched across the horizon, it was not an omen. If any were brave enough to board the ship, they would find no one - no living soul left alive on the ship, the only souvenier of its trip the king's head, moored to the helm with ice. This is no omen. This is no warning.
We are already here, Phoenix. This is a message.