|This article is about the structures on Cadia, for the Necron mobile weapons emplacement see Necron Pylon|
The Pylons are monumental constructions of unknown origins on a number of planets near the Eye of Terror usually found near the Cadian Gate that hold back the tides of the Warp. These structures are one kilometre tall, half a kilometre under the earth and half a kilometre on each side. They have an intricate system on tunnels bored into them, which are impossible to map, as even the smallest servitor never returns from a journey within them. There tends to be a complex arrangement of them across a particular planet, such as those on Cadia.
They are believed to be of Necron design,[Needs Citation] intended to influence the warp in their immediate area, this is thought to be the reason that there is a relative calm area of warp space, now called the Cadian Gate, which is the only safe thoroughfare in the area. Inquisitor Quixos attempted to construct his own in order to further his own Radical goals.
Pylons can be reduced to ruin through overloading them with massive amounts of Warp energy, such as an influx of Daemons. Abaddon the Despoiler intends to overload the Pylon network on Cadia to allow the Eye of Terror to envelop the worlds of the Imperium. Known as the Crimson Path, without these Pylons even Terra itself runs the risk of being swept up in the Eye of Terror.
- 1: The 13th Black Crusade (Background Book), p. 15
- 2: Codex: Chaos Space Marines (6th Edition), pp. 19–20