Four dimensional drones are robotic starfighters which can travel through four dimensional space. The Supreme was the first known entity to use these drones in 184001 CE. However, they've existed for millennia under the control of the Alliance. The drones were used extensively during the War of the Ancients. Currently, every known empire can use them.
General
Creation
In 184001, The Supreme created the fleet as a last-ditch attempt to best The Seekers. It was losing badly in the Tloinin Galaxy and was barely managing to retain control over the rest of its empire.
Production
The Supreme took five specially made drones and moved them to 4 dimensional space with carefully controlled Gravity Wave Wormhole Disruption. These drones were unable to move in four dimensions as they had thrusters designed to work in 3 dimensional space, as they were merely three dimensional objects.
This results in the drone being unable to move four dimensionally, instead, only moving in three axes. One drone is put in 4D space that is able to move in the x, y, w, axes, while another one can move in the x, y, and w axes. The two drones automatically find each other and latch together with a magnetic field. The combined droned can move in four dimensions x, y, z, and w. (Note all four of these are spacial dimensions.)
Visualization
Visualizing the process precisely is next to impossible for all biological life, as they are merely three dimensional organisms. A few visualizations have been created for the purpose of describing the process easily.
Imagine a 2 dimensional plane. This plane has only x and y axes. A 2D being on the plane figured out how to move square shaped drones into 3D space directly above the plane. The drones are only able to move in two dimensions. So the drones need to be positioned such that one can move in the z axis, at the expense of another axis. One square is pushed off the plane in such a way as to rotate it off of the x axis (or y). The drones can move in the y and z axis now, while the other can only move in the x and y. The two can latch together and move in all three dimensions.
Effectivity
Each drone was able to move in four-dimensional space as they were four-dimensional objects. Therefore one could easily move out of three-dimensional space to be invisible. Then move back into three-dimensional space to fire, and then quickly move back into four-dimensional space. Also, each drone could intercept ships traveling through wormholes and several battles took place within wormholes.
Drawbacks
Four-dimensional space and physics are impossible for a biological life form to actually comprehend. Even computers programmed by biological life are not up to the task. A computer would need to program itself to actually be able to process what is happening. Only a super intelligence could ever hope to pilot one. However, they take tremendous amounts of energy to create, about the power output of a Dyson sphere per second for each kilogram of four-dimensional material created. It takes about 10 seconds worth of power from a Dyson swarm to do the same thing.
This drawback did not stop The Supreme, and later the Commonwealth and the Confederacy. They all appear to have some fleet of four dimensional drones
Even The Supreme experienced great difficulty when controlling the drones at first, but after practicing and experimenting with four-dimensional physics The Supreme mastered the technique. It takes 1000s of times more processing power per four-dimensional drone than for a three-dimensional drone.