The Forge World's military forces reside within the Crown and it is from there they deploy when Graia is endangered. However, the entire vast megastructure's engines can move the Crown and also allow it to enter the Warp. This ability is used to not only transport Graia's forces across the galaxy, but also allows the Forge World to exploit the resources of distant worlds. Once a suitable resource-rich world has been discovered, the Crown's chorazine shunt thrusters lock it into a stationary orbit like a tick. Fleets of Industrial Harvesters then descend and begin leeching the world of its assets, for Graia to consume. Should an enemy be foolish enough to to attempt to board the Crown, during this process, the megastructure's production subroutines will immediately adapt to the threat. Hundreds of freshly built Skitarii and Servitors will begin pouring off the Crown's production lines every minute, while Servo Carts will deliver vast quantities of ammunition to its immovable defenders. And even as the invaders are being fought, the plunder of the world below the Crown will continue unabated.
While the knowledge of the Crown's ability to move on its own is suppressed by Graia as much as possible, both the Necrons and Chaos Daemons know of it. This has led both foes to repeatedly attack the Crown and Graia's forces have fought to defend it from being overrun or captured. Yet so great an advantage is this immense battle fortress, that the logical value of its use to Graia far outweighs the potential risks of losing the Crown to a hostile force.