Say, if someone, who is an Animagus, under the effects of a Polyjuice potion turned into his animal form and then back into human again, would he revert back to the Polyjuice-form or his true self?

 

Why do you ask questions for which you know there is no answer.

Obviously that situation never occurred in canon. Any answer would be complete speculation.

 

To confound you perpetually.

And because I was merely being curious, and even speculation would be alright as this is, after all, the sub-forum for Fanfic Discussion.

Think of it as me asking your opinion on the outcome, rather than expecting someone to hand me down Rowling's own word on the matter.

 

Fair enough, I'll keep to the guidelines for asking questions the next time something pops into my head.

 

My version, should it become an issue in a story:
The potion takes effect when it is consumed and lasts around an hour depending on brewing skill. If an animagus needed to change form while uunder the influence of the potion, he could, but probably would end up flushing the rest of the potion's effects away in doing so. He reverts to his normal appearance. Most recent transfiguration wins.

Taking Polyjuice of someone who is an animagus doesn't grant you the ability- it's a self-transfiguration that's very comfortable for the one who found that form and doesn't carry along knowledge from the donor with their appearance.

That said, much of magic is hinged on understanding and belief, so a person who takes Sirius' form through polyjuice might attempt to self-transfigure into a dog and be successful, but he wouldn't necessarily look like Padfoot and probably wouldn't retain their human intelligence. (why do I see Ron trying this?)

 

Well, we know that when human attempts to transform to animal via polyjuice, transformation will be permanent (albeit reversable) and drinker will be disfigured, that is stuck between his normal human appearance and that of said animal.

I assume that this mechanism works both ways, so if an animal would try to transform into a human, it would end up being disfigured and permanently transformed. So, attempt of an animagus to transform into his animal form while being under effect of polyjuice potion would probably end up being unsuccessful and this hypothetical person would have to seek out St Mungo's.

 

I would say a person who has not developed the ability to transform themselves into an Animagus would not be able to turn into one, provided they were Polyjuiced as a person with that ability. Vice versa, a person who could turn into a bird, for example, would not be able to complete the transformation in another's body, as they would be unused to it.

I would say that it's POSSIBLE to do it, but that you would need to consistently inhabit another person's body -- think if Crouch and Moody were both able to transform, and Crouch continually used Moody's body and worked at transforming into Moody's animal. Of course, he'd only be able to use that form while he was Polyjuiced into Moody.

Then again, it's also plausible that it's impossible.

 

I don't think a person's magical abilities are tied to their body but rather to their soul.* The only instance of a person gaining a magical ability we know of is Harry becoming (and then losing) a parselmouth, and that involved no change in his body but rather magic involving the soul. Similarly, when Voldemort's body was destroyed and he made himself a new one, his magic carried over identically. He was even able to perform some types of magic without a body.

So that's the issue of who has the ability.

With that in mind, I'd say that an animagus under polyjuice should still have the ability to use their ability normally. Even if the wizard they are impersonating is also an animagus, they should still transform into their animal, not the animal of the impersonated wizard.

The issue is the return. Whether you return into the polyjuice form or your normal form depends on the mechanics of the transformation, which are unknown.

Possibility A is that the return transformation works as "reverse the previous transformation". In that case, you'd return to the polyjuice form, not your true body. This then becomes complicated if the polyjuice time has expired. Was the polyjuice put on pause? Or do you just return to your regular form if the polyjuice has expired? Or does it all end in a horrific accident?

Possibility B is that the magic is "turn me into my human body" magic. In that case you'd transform into your regular form, not your polyjuice form. Essentially you're not undoing the animagus, but rather actively transfiguring yourself into yourself.

Possibility A is how I'd say regular untransfiguration works. I've argued elsewhere that untransfiguration isn't cancelling transfiguration magic which is still active, but rather reversing a transformation like the reparo charm reverses damage.

Possibility B seems to be impossible for regular transfiguration to achieve, because if complete bodily transfiguration was possible it could be used to deage people, and to create new human life via magic, e.g. by transfiguring a rock into a human. (This was essentially the premise of Lords of Magic).

However, that doesn't mean that Possibility B is ruled out for animagi, because we know that the animagus transformation is different from regular transfiguration. Through a WOMBAT test we know that it also involves an element of charms, and this may be it. Creating human bodies may be impossible for transfiguration, but forcing a person into their true form is possible in Charms: the homorphus charm.

On balance, I'd say that the animagus would return to the regular form, not the polyjuice form. If not that, I lean towards "horrific accident" where two powerful magics do not play well together.

*Yes, there is a gene involved somehow, but that doesn't mean that magic is essentially biological. The "magic gene" could trigger some change in the soul during development, for example.

 

I tend to take things like this literally.

Explanation:

What is an Animagus? - Someone who can turn into an animal using some advanced transfiguration.

What is the Polyjuice Potion? - A potion which allows one person to acquire the appearance of another person for 1 hour (this includes all details even scars).

These two things do not contradict each other. One uses Transfiguration and the other one uses Potions.

So, the answer MUST be:

If Sirius Black drinks the Polyjuice Potion to look like James Potter and then turns himself into a dog using his Animagus abilities, upon transforming back he'll look like either himself if an hour has passed or James Potter if an hour did not pass.

Well, that was easy.