The Imperium sent Fleet Admiral Lord Byron Van De Castile, commander of the Apocalypse Class battleship Aquila, to deal the coup de grace. If that was not enough, the Lamenterís chapter was in his rear pocket. Even depleted from its battles with the Tyranids, such a force was potent, especially in ship to ship fighting. Admiral Van De Castile had every intention of exploiting this strength. He chose to intercept the Ork a great distance from the planet rather than allowing them to land and slogging it out with Imperial Guard.
The Orks would open fire first as the two rows of ships; the Orks in bunched, mob formation and the numerically superior Imperials flying in battle groups for mutual support. The Orks had little chance of hitting anything at such distance with their rockets. The Imperials returning fire once they had a good firing solution.