Doctor Who is introducing a brand new type of Dalek. It's hard to imagine Doctor Who without the Daleks. The Daleks first appeared in Doctor Who's second story, back in 1963, and in truth they're a major reason for the show's success and longevity; there's something undeniably appealing about the irredeemable killing machines, the perfect villains because they are motivated by a genocidal desire to prove themselves the supreme beings of the universe.
Dalek mutants may (largely) stay unchanged, but the Daleks are always updating their technology. Over the years, this has led to the Daleks developing a number of specialized units; the classic series introduced the destructive Special Weapons Dalek, while Doctor Who's 2022 Holiday Special introduced the brutal Executioner Daleks. But it seems Doctor Who is about to introduce a brand new type of Dalek in Big Finish's upcoming audio-novel, "Emancipation of the Daleks."
Big Finish has released an official synopsis for the audio-novel, written by Jonathan Morris and due for release in July 2022. According to the synopsis, the Twelfth Doctor and his companion Bill Potts almost collide with a Dalek war saucer in the time vortex; the Doctor manages to dodge the Dalek ship, but it crashes upon Earth in the near past, resulting in the creation of a brand new timeline. When the Doctor and Bill return to Earth, they find the planet apparently conquered, in a grim parallel of 1964's "The Dalek Invasion of Earth." Just as in that dystopian future timeline, the ruins of Earth are patrolled by Robomen - but now they're assisted by Dalek security drones piloted by Dalek mutants. Here's the full synopsis:
"Bill Potts has an unexpected visitor: another Bill Potts from twenty years in the future. Bill summons the Doctor, who confirms that the other Bill is the genuine article. She has come to see her younger self for a reason... but she can’t say what it is without creating a paradox!
Moments later, the TARDIS Cloister Bell sounds. A damaged Dalek war saucer is travelling back through the time vortex on a collision course. The Doctor dematerialises the TARDIS to avoid it, only to cause the spaceship to crash-land in Earth’s recent past. When it re-materialises, the TARDIS is now in a world altered beyond recognition. The city of Bristol has been reduced to rubble, save for an interstellar rocket construction site and a top-security research complex. The complex is guarded by ‘Robomen’ and flying security drones piloted by Dalek mutants.
The Doctor quickly realises what has happened. History has been changed, and the Daleks have conquered the Earth, enslaving the human race.
He couldn’t be more wrong. And Bill is about to discover that her past, present and future are no longer her own."
Time is fluid in Doctor Who, which explains why Doctor Who's continuity is so confusing. In this case, it seems the crashing of the Dalek war saucer has created a brand new timeline, one in which Earth apparently fell to the Daleks in the early 21st century. But the synopsis hints everything is not as it seems, and certainly the audio-novel's title - "Emancipation of the Daleks" - suggests there's a lot more going on than the Doctor initially believes. It's possible the Dalek war saucer the TARDIS nearly collided with was actually a rogue, containing Daleks who had somehow rebelled against the Dalek Emperor.
The Dalek security drones are just as curious. The design shown on the audio-novel's cover is oddly reminiscent of the Toclafane, future humans who were twisted to the Master's will and weaponized against the Earth in the David Tennant story "The Sound of Drums." This may well suggest the Daleks the Doctor is encountering in "Emancipation of the Daleks" are essentially some sort of evolutionary offshoot, creating using human genetic samples - in which case they could be very different to the Daleks traditionally seen in Doctor Who.
Source: Big Finish