Borg supercube crisis

The Borg Supercube Crises was a series of engagements between a Federation Fleet and a Borg Supercube that occurred in 2380.

Reactivation of the Cube
The crisis started when the Borg Supercube in Sector 10 began to regenerate itself. Taking Kathryn Janeway as its new Borg Queen and assimilating the Federation Science Vessel USS Einstein, the cube headed for Sector 001, with the intention of absorbing, rather than the less-efficient assimilating, Earth and, later, the rest of the Federation. However, the reactivated cube drew the attention of Seven of Nine who heard the voices of the reactivated Borg. After evading the USS Thunderchild, Seven rendevoused with Captain Jean-Luc Picard on the Enterprise (1701-E) to devise a defense against the cube.

Sector 108 Stage
After the cube's reactivation was discovered by the Thunderchild, which the Cube absorbed directly into its hull, a Federation fleet engaged the Cube at Sector 108. The fleet targetted the weakspot of a cube discovered by Picard at the Battle of Sector 001 several years earlier, with no effect on the Cube. The cube then accelerated towards the Federation fleet absorbing the majority of the starships into its hull. Dozens of starships were lost to the cube, however several, including the USS Nautilus, managed to escape. After 97 seconds, the Federation fleet was either scattered or destroyed and the supercube continued on its way towards Earth. Later, this battle became known as the Slaughter of Sector 108.

Sol System Stage
After decimating Federation forces in Sector 108, the Borg supercube absorbed the entire mass of the planet Pluto, before moving deeper into the system. Once in Earth orbit, the cube informed the Federation Council that if they delivered Jean-Luc Picard and Seven of Nine to the Cube, then the Borg would leave Federation space. After intercepting a communique between the Enterprise and Starfleet Command, the Queen realised that Picard and Seven were heading to Trophy World to activate the Doomsday Machine. Unwilling to send the cube to intercept the Enterprise, the Queen flew the supercube into Sol to gather enough mass to spawn 6 smaller starships, which then moved to hold Earth hostage and intercept the Enterprise. After this occurred, Federation Ambassador Fox, acting against the recommendation of Starfleet Command, attempted to negotiate a cease-fire with the supercube, however, his runabout was destroyed by the supercube.

The Tide Turns
Once the cubes small starships had reached and engaged the Enterprise, Seven of Nine managed to reactivate the Doomsday Machine by becoming its new pilot. After destroying the starships attacking Enterprise, the Doomsday Machine took the Enterprise in tow and headed to Earth at very high warp speeds. On the outer edge of the Sol System, the two ships rendevouzed with the USS Excalibur and a small Federation Task Force, where Picard took command and ordered the Federation ships to engage the Borg starships whilst the Doomsday Machine engaged the Cube. Whilst both the Doomsday Machine and the Federation Task Force were able to inflict considerable damage on the Borg forces, they were soon overpowered. The cube, now greatly reduced in size thanks to the Doomsday Machines antiproton blaster, was able to manouver behind the Doomsday Machine where it began to absorb the Planet Killer, incorporating the impervious Neutronium hull into its own structure. However, a backup plan was already in motion in Seven of Nine, who had been injected previously with the Endgame Virus. A firewall devised by the Borg Queen originally prevented the virus from infecting the cube, but Janeways long dormant personality emerged long enough to allow the supercube to become infected with the virus, which ultimately destroyed the supercube and its starships, however, the assimilated USS Einstein managed to escape the Sol System.