To build either type of fusion cube the Borg had first to have built a fusion hub within the local area of space they were operating. Once the hub was developed the Collective could then select eight cubes which would place themselves in a careful formation and fuse. Tactical fusion cubes had a crew of thousands, were heavily armed and had powerful shields, making them one of the most powerful vessels in the Borg fleet. A tactical fusion cube could effortlessly repel attacks from even the most formidable opponents - easily outgunning and overpowering even a starbase.