I have made much of the capabilities of the Astartes in their prosecution of war but although it is fearsome, it can at least be understood. The same cannot be said of what we came to know as the Machinedeath where such cataclysmic destruction were unleashed upon the world of Null as to almost defy mortal comprehension, for it was here that Volnoscere would unleash the full might of the Argyntum Stellae against the engines of the Legios Punica and Validus which had been arrayed by the tyrant Eynoch in a misguided bid to deliver a coup de grâce against the Legion. 

Engines. Such a term seems so woefully inadequate to accurately convey the might  and scale of such machines. Machines that wield weapons of such potency as to be able to slay entire companies of infantry and render armoured columns to burning wreckage in but a heartbeat. I have heard that the graduates of the Collegia Titanicus and their kin in the Adeptus Mechanicus call them God-Engines and though I have rejected the deification taught by the Symbolum Imperiale in all its forms, in the light of the destruction wrought amid the dust and ashes of Null I can see where such reverence springs from.

That the Machinedeath was a costly mistake for Eynoch and his masters was but small consolation when weighed against the losses of men and materiel to the Legion and their allies, for in this undertaking had the Argyntum Stellae been joined by pledged contingents of the Pracones ArgentiHæredes, Scillisus Domini, Inanis Barones, Piscis Rubrum, Unguibus Vyridis and Lacunignis all of whom committed armoured fighting vehicles up to and including those of superheavy classification to battle, for little else could have stood against the foe that awaited them upon the wastes of Null and emerged victorious... 

Illiatariu. C., Rememberancier Documantist Minoris. To Walk Among Demigods. A Treatise Upon The Nature of The Argyntum Stellae., Published 863.M33, Sector Heliopolis, Segmentum Pacificus.