In "The Time of the Doctor", we see Matt Smith's Doctor go out with a bang as he uses (apparently excess) energy from his regeneration to destroy the Daleks that have besieged him. This appears to be an incredibly powerful piece of destruction, yet seems to have absolutely no effect or consequence on the Doctor (i.e. he still has enough regeneration energy left in order to subsequently complete the regeneration into Peter Capaldi's Doctor, there is no apparent "cost" to this exercise).

This seems counter-intuitive to me, as you would think that a regeneration would have just enough energy for a complete regeneration and no more. Is there a precedent for this in canon that might explain how Matt Smith's Doctor was able to pull such a stunt as it doesn't seem to make much sense?

One thought that occurs to me is that Matt Smith's Doctor may have somehow used up more than one regeneration’s worth of energy in order to achieve all that he did in "the Time of the Doctor", however this is pure speculation on my part. Alternatively, perhaps the first regeneration of a cycle of regenerations (this being a new, 2nd cycle for the Doctor) is more powerful than the others? (Again, speculation.)

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    I don't think so. At least not to that extent. Part of the answer might be found here : scifi.stackexchange.com/questions/46861/… Commented Jan 1, 2014 at 11:00
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    IMO it's just a really bad incident of really bad writing, i.e. Moffat didn't find any easier or more logical way out of it (or at least a less dramatic one). However, there has been at least one other incident in New Who where the Doctor used regeneration energy vs. some Daleks(?). However, I don't remember the exact episode. I think it's been The Stolen Earth? Might be wrong on this one, though. It's been like "not good attacking someone while he's still regenerating" or something along those lines.
    – Mario
    Commented Jan 1, 2014 at 11:12
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    Ah, sumbuddyx's answer includes the right reference. It hasn't been the Doctor himself. It's been River during Let's Kill Hitler.
    – Mario
    Commented Jan 1, 2014 at 11:24
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    The Doctor also did it in The Angels Take Manhattan, to heal River's wrist.
    – Mr Lister
    Commented Jan 1, 2014 at 12:24
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    good examples of regeneration energy being used for something other than regenerating a timelord, but I'm not sure we can say they are quite the same as taking down so many Dalek ships with huge blasts of energy! It seems there may well be no instances of this kind of thing happening before. Commented Jan 1, 2014 at 12:41

3 Answers 3



  • The Tenth Doctor regenerated and causes enough damage to the TARDIS that it needs to regenerate in The End of Time Pt 2.
  • River Song regenerates and is able to use regeneration energy as a weapon against the Nazis in Let's Kill Hitler.


  • The Tenth Doctor is able to re-grow a hand because he has an excess amount of energy, which seems to agree with the basic point of Eleven being able to use up some of his energy and still regenerate. You might even include the whole Metacrisis Doctor, in that he used enough energy to heal himself and then built himself a whole duplicate Doctor with the spare energy.

  • And possibly as a sort of vague mention, the Ninth Doctor told Rose to get back while he regenerates, as if to say the regeneration energy is destructive and would be hazardous to her health, which I mention only because it might be the first time regeneration was seen as dangerous. I don't recall it ever being a problem in classic Who.

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    These examples do not seem like the same HUGE level amounts of damage that #11 used to destroy ships. Commented Jan 1, 2014 at 11:28
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    interesting points, the River Song one seems like the closest however (just playing devil's advocate here) possibly the exact nature of regeneration would be different as River is half human. Re the Tenth Doctor, I had always thought this was not an example of excess energy, but rather of the redirection of some regeneration energy (as the siphoning off of regeneration energy into the hand meant that the Doctor retained his appearance, as David Tennant). The duplicate doctor is not a full copy of the doctor. Commented Jan 1, 2014 at 12:05
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    As for the other two examples re the Tardis and 9th doctor, both good points but are they equal to what we saw in the Time of the Doctor? I have not seen much Classic Who (started watching when New Who started) so it is interesting that you would say this may be something that was introduced at that time. Commented Jan 1, 2014 at 12:09
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    @MeatTrademark: No, they are not the same HUGE amounts but then, neither of those characters had just had a whole new cycle of regenerations pumped into them. Since we have never seen what it is like when a Time Lord receives a new cycle, there did not need to be a precedent, although there was.
    – Amy
    Commented Jan 2, 2014 at 6:55
  • @Amy That was exactly my point. We have not seen it before because this is different. Commented Jan 2, 2014 at 8:34

No, there is no precedent for this.

The most destructive we've seen a regeneration before was Ten's, which destroyed the TARDIS console room for... we know not what reason, though there's speculation that it's because he delayed the regeneration for so long after getting poisoned. Seemed more like an angsty tantrum to me, or a metaphor made literal. River Song managed some kind of bizarre shockwave thing, a la Riddick, which we've also never seen before or since. Both Ten's explosion nor Song's shockwave were totally unlike the directed-force beams of Eleven's regeneration.

There is an association of regeneration with destructive powers: the Master once attempted to re-charge his regeneration cycle by... well, by hugging a black hole. He would either die or get a new set of regenerations, but he was interrupted so we didn't get to see the final result. The black hole was the Eye of Harmony, a collapsed star which powered all of Gallifrey's advanced technology.

However, prior to Ten blowing up the console room, regenerations themselves were never violent. (Not least of all probably because it's easier to do fade-frames on someone who's holding still, but Doctor Who never let the limitations of technology get in the way of trying to show off a cool idea.)

We've never seen a Time Lord get a second set of regenerations (though we know it's possible because the Master and the Valeyard both tried, and the Council once bribed the Master with a new set but didn't follow through), and we have nothing in screen canon on which to build constructive theories about the quirks of the process. Non-screen sources have speculated that the limit is due to the photo-copy effect: after a while the regeneration process produces new bodies with too many bugs and flaws to be worthwhile. On the other hand, The Five Doctors implies that it's because Rassilon knew if Time Lords were given true immortality they'd be even more insufferable jerkfaces than they already were.

  • looks like there is no precedent for this then, as both this and the other answer show there are similar examples of regeneration energy being used for something other than regeneration, though not to the same destructive end as is seen in the Time of the Doctor. It seems any explanation for this would have to come by way of retcon from subsequent episodes which have not been written yet. Commented Jan 1, 2014 at 12:38
  • Rassilon is already truly immortal from what I read about him... some say he's actually a Vampire... Commented Jan 2, 2014 at 16:56
  • @DoctorWho22 Screen canon is not explicit on the matter, and it's not really relevant to the question anyway. Whether or not Rassilon is immortal, he made sure that other Time Lords would not be.
    – BESW
    Commented Jan 2, 2014 at 21:13

Well, the energy destroyed the TARDIS when he regenerated in the End of Time, so it's probably due to the sheer buildup and power of the energy.

  • This seems to be pure speculation and doesn't really address the question. If you could add canonical facts to support your point though, that would be great! Commented Apr 16, 2014 at 1:19

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