Revenge of the Cybermen - S12-E5
Plot hole: The Vogans live on a planet made of gold. They helped develop the gold weapons that defeated the Cybermen. They know the Cybermen are coming and live in a state of paranoia about that eventuality. So why in the world do they attack the Cybermen with useless projectile weapons instead of "glitter guns" or some other gold-based weapon?
Revenge of the Cybermen - S12-E5
Visible crew/equipment: Quite a few times during this story arc you can see Vogans without their gold eye make-up so you can see human coloured eyelids when the rest of them is all brown.
Revenge of the Cybermen - S12-E5
Continuity mistake: The use of gold against the Cybermen is wildly inconsistent in this episode. It is said that it suffocates them. Yet Cyberman have been seen functioning perfectly in vacuum ("The Moonbase" and "The Wheel in Space"), it affects the Cybermats, who are little more than metal drones, and it affects the Cybermen's radar, which does not breathe.
Revenge of the Cybermen - S12-E5
Continuity mistake: At the end of "Genesis of the Daleks", the Doctor was wearing his big brown overcoat. However, at the beginning of this episode, he is wearing his red jacket again.
Revenge of the Cybermen - S12-E5
Revealing mistake: At the climax of episode four, the Beacon plunges close to Voga and orbits very fast before the Doctor manages to break free. The planetscape that appears on the screen is quite obviously a revolving drum with bits of clay on it.
Revenge of the Cybermen - S12-E5
Plot hole: Sarah is transmatted down to Voga after being injected with alien poison by a Cybermat. According to the Doctor, the transmat will recognise Sarah's human molecules and separate and reject the (non-human) poison molecules. As clothing fabrics tend to made of non-human molecules, how come Sarah and Harry didn't arrive on Voga stark naked?
Revenge of the Cybermen - S12-E5
Other mistake: Shortly after the Doctor makes his speech to the Cybermen about how pathetic they are, you can see a Cyberman's head wobble.
Revenge of the Cybermen - S12-E5
Continuity mistake: For a supposedly emotionless creature, the Cyberleader is easily provoked to a fit of rage, including throwing the Doctor around the Beacon.
Answer: In 'The Five Doctors', three separate Cyberleaders are definitely used. So it's likely that Cyberleaders are like unit commanders, of which a fair-sized army might have several.
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