With The blood Ravens starting to withdraw the Dark mechanicus threw themselves into punishing the Imperial force hoping to turn an orderly withdrawal into a route. The forgefiend, Heldrake, and Kastellan robots poured fire into the building where Asimoth sheltered. The hail of fire killed another marine and set the building ablaze as Asimoth pulled back from the battlefield.
The helbrute with the plasma cannon opened up on the assault marines blowing apart all but one of the blood ravens before charging in and crushing the lone survivor with it's power fist.
The Maulerfined charged into the tactical marines crushing a number of them but not before one of them set the Helbrute ablaze with a krak grenade. The Blood Ravens promptly disengaged. They had determined the value of Site 1437 and it's purpose. Cleansing the site would be a major undertaking for a far larger task force than they had at their disposal. The Dark mechanicus would hold site 1437 for now, but the Imperium would return again one day in strength.
Special thanks again to Justin Grandpre (seen below) for all his help with this battle report including the use of his excellently painted Blood Ravens!