Nyadra'zatha, the Burning One, had long desired to carry his eldritch fires into the Webway and beyond. He enabled the Necrons to gain access to the Labyrinth Dimension, showing the Necrons how to breach its boundaries through a series of living stone portals known as Dolmen Gates. As a race bereft of psykers, the Necrons are incapable of Warp travel, without access to the Webway, they would be forced to rely on slow-voyaging stasis-ships, dooming them to isolation within the galaxy.