The Borg tactical sphere was a vessel of the Borg Collective. Just as its less combat-capable sibling, the Borg sphere, its diameter was 600 meters and it could carry 11,000 drones. The Tactical Sphere was a more powerful and more heavily armored version of the standard Borg Sphere. (TNG video game: Starfleet Command III) The Borg Collective used tactical spheres to conduct first contacts with races suspected of posing a threat to the Collective, but could not pose a threat sufficient to warrant the use of a Borg cube.