Star Trek: Every Borg Ship Explained

Another class of starships that only appeared in one episode are Borg Scout Ships.

One Scout Ship crashed into a moon in the Argolis Cluster, and was found by the Enterprise-D in the Next Generation episode I Borg. The entire crew was killed upon impact, apart from one drone, Hugh, who later regained his individuality and rebelled against the Collective.

Later in the episode, another Scout Ship came to pick up Hugh, and the Borg known as Axum said he was stationed aboard a Scout Ship in the Voyager episode Unimatrix Zero, but the only one we saw onscreen was the crashed vessel near the beginning of the episode.

It appeared to be the smallest Borg starship, the name suggests they're likely surveillance ships like the Probes, but shaped like a cube. Also, the fact that only one drone survived the crash suggests that the crew complement is quite low.