The Horus Heresy - Araknae Quad Accelerator Platform (31-125-W) - Used

Every Space Marine Legion had a number of standardised fortifications at its command that could deploy from orbit to create networks of defences, and footholds from which their forces could slowly expand to claim new territory. The Araknae Quad Accelerator Platform is one of the largest, a huge gun emplacement armed with quad accelerator autocannons that projects a protective forcefield around it thanks to its atomantic pavise.