I think they are servitor Missile Defense system.By the by, in the second episode what are those metal orbs flying on each side of the shuttle?
I.e. Some poor human Got glued into a missle defense system, to be the computer for it.
Heavy Laz weapons, THe multi lazer started to damage the ceramite on the plate.What even penetrates space marine armor? I know the dudes are walking tanks, but damn.
Anti armor, repeatedly works
But marine armor in lore is supposed to basically be resistant to ALL small arms fire, sustained anti armor fire will down em. or heavy ordnance. basically anti tank guns to take em out.