Expanoids

The Expanoids were a subcategory of Simulants, who wished to enslave humanity rather than destroy it like most other Simulants.

As the entire plot of Twentica was a parody of the film, Star Trek: First Contact, the Expanoids are a homage to the Borg.

Their leader, 4 of 27, was portrayed by Kevin Eldon. Whilst the later introduced Expanoid, 3 of 63, was portrayed by Alexis Dubus.

Role in the episode
The Expanoids stop the crew, taking a future Rimmer hostage, but releasing him in-exchange for the Casket of Cronus, possessing the capability to travel dimensions. After they leave, its revealed our Rimmer post-trade was the Rimmer taken hostage, who is immediately taken and brought back. Having overheard them, however, he knows they've traveled to an alternate Earth to manipulate history; as such, the crew ride the Expanoids' time hole and crashland on Earth in the United States.

After walking into town, the crew discover its the 1950s and the Expanoids have enslaved humanity, banning technology to prevent resistance to their rule. The crew find a speakeasy, which here is home to scientists, and set about to find Albert Einstein, who they are told wanders the streets as a bum, and task him with fixing an EMP to knock out the Expanoids.

The bring back who they believe to be Einstein, but is really a homeless man named Bob the bum. The police arrive and figure out its a speakeasy, calling Expanoid backup. The Expanoids arrive, however Bob figures it out in the nick of time and kills the Expanoids. They switch on the EMP to go global in 10 minutes, just enough time for the crew to hop back onboard Starbug and travel to their original dimension and back to Red Dwarf.

Red Dwarf XI - The Game
In the Twentica adaption for the mobile game, Red Dwarf XI - The Game, the Expanoids are enemies to the crew. In the first level, which does not happen in the episode itself, you play as Rimmer following his capture and sneak through their ship, blasting Expanoids with an acquired bazookoid, before being captured by them and used as their hostage.

Later they serve as enemies when you arrive on the alternate Earth, playing out much the same as the episode.

Red Dwarf XII - The Game
In minigames reminiscent of Temple Run, the Expanoids serve as occasional enemies when running through the corridors of several ships from Series XII. An Expanoid is also an unlockable playable character, though the Expanoids remain as regular enemies.