Disaster / Destruction
At the start of the Greenskin War the Aegean Hypercomplex - a massive and vital industrial sector, home to billions of citizens and the primary manufacting and resource gathering operation on the edge of the system - was on the opposite side of the system from the Ork invasion point, and as such were a vital fallback and resupply location. However, as the war progressed, orbital mechanics brought the Aegeans closer to the Ork asteroid base. Somewhere around the year 800.M41 the Orks used a superweapon that tore open space, destroying the hypercomplex, killing billions of people and shattering the supply of material for the war.