Holosphere
From Warhammer 40k - Lexicanum
Holosphere was a Necron broadcasting device, used by the Overlords to address multiple planets simultaneously.[1]
Overlord's throne emitted the holospheric field that lit the overseer and captured the image that was then transmitted away. On the receiving end, tomb worlds had projection cones mounted in every key location across the world, projecting a large figure of their overlord and vocalising the message.[1]
