Mass Effect: Ghosts
The Veil’s total opacity prevents Council intelligence from surveying Geth activity. Theoretically, the Geth could be preparing a devastating attack against which the Council could be defenseless, or the Geth could have died out, so that the defense budget against them could be gaining the Alliance nothing but economic ruination.
Despite fears of Geth, prospectors do occasionally mount salvage ventures inside the Veil; one ended in tragedy. Using technomental domination, the Geth drew the team into the Veil before aiming them back as Husks at the organic society that produced them.