Doorway to Hell (comic story)

Doorway to Hell is set after the Doctor and the Master's "affair with the Daleks and Draconians", referring to Frontier in Space, the last appearance of Roger Delgado as the Master prior to his death.
The appearance of the Master's regeneration resembles the effect used on television since The Parting of the Ways in 2005. The shot of the Master looking at his hand, meanwhile, is closest to a shot from TV: The Time of the Doctor.
The fact that Roger Delgado's Master is shown regenerating either retroactively establishes that the decayed Master seen in TV: The Deadly Assassin and The Keeper of Traken is not the same incarnation as that played on TV by Roger Delgado, as had previously been implied in The Deadly Assassin, or that this was simply the botched regeneration into Pratt/Beevers' Master, which burnt his body to a crisp. This seemingly contradicts PROSE: Legacy of the Daleks, but, since we are not shown his new form, he could have possibly somehow kept the same Delgado body.

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Continuity

The Master is aware of the unfortunate events the Collins were involved since meeting the Doctor:
- Lloyd's body was changed by an alien bacteria, while Devina had to watch him nearly die. (COMIC: The Pestilent Heart)
- Max was abducted by Skadi and Broteas, while Jess was hunted down. (COMIC: Bloodsport)
Through his TARDIS' scanner, the Master watched the Doctor's TARDIS explode over Brixton. (COMIC: The Pestilent Heart)
The Doctor is from far in the Master's future, and says his age is four billion. Ohila had previously mentioned the Doctor had spent four and a half billion years inside the confession dial. (TV: Hell Bent) However, the Doctor would later describe his age as 2,000. (TV: Smile, et. al)