Cardinal Rassilon was the one who modified Time Lord DNA to allow regeneration. According to the wiki he also input a parameter of twelve regenerative cycles to avoid decaying biogenic molecules.

Seeing as The Doctor has had his 12 regenerations but was given extra regeneration energy by the Gallifreyans, does this mean his molecules could start to deteriorate in future incarnations?

I don't know how canon the Cardinal Rassilon information is, and if the current producers would follow that logic.

  • 1
    Bear in mind that an important element of Dr Who is "Wibbly Wobbly Timey Wimey". In other words, a potential problem like the one you just mentioned can be dealt with by literally anything. Commented Jul 17, 2017 at 12:59
  • How can we know for sure, given they've so explicitly chewed the fixed number of regenerations rule? Commented Jul 17, 2017 at 13:00
  • Regarding the flag, this only seems primarily opinion based because we have no canon info and Dr Who just does whatever it needs to do for the plot. Which I think would be better as an answer than implied though a close reason. Voting to leave open.
    – amflare
    Commented Jul 17, 2017 at 13:39
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    "Primarily Opinion-Based" is also the vote used when invoking the "Future Works" policy. The votes are valid if you consider the fact that we don't have canon information now, but may gain some in the future. Commented Jul 17, 2017 at 13:46
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    Also, to the OP, as far as Doctor Who is concerned, there's no such thing as an official "canon". Commented Jul 17, 2017 at 13:51

1 Answer 1


As long as the show is on the air, they'll figure out a reason to keep The Doctor regenerating, so it's unlikely this new regeneration cycle will suddenly begin falling apart.

The show, particularly under Moffet's direction, does seem to be trying to stick to old Who "canon" when they can manage it. The 12 regeneration rule could have been silently dropped, but they stuck to it when it was time for Smith to exit the show.

Note, however, that we also know from old Who that the Time Lords can give a new cycle of regenerations (they offered it to The Master at one point). Most likely, this is what they did for The Doctor -- they gave his DNA a reboot and he has 11 more Doctors regenerations left to go.

  • "it's unlikely this new regeneration cycle will suddenly begin falling apart" True, but it could possibly still be a plot point at one point or another. However, I do think you're right that his regeneration "battery" has been recharged and that he has 11 more to go.
    – Flater
    Commented Jul 17, 2017 at 14:57
  • Unless they accidentally overcharged his battery and now he has no idea how many he has left ;) Commented Jul 18, 2017 at 9:55

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