In Hell Bent 12 and Ashildr meet at the end of the universe . Ashildr claims she is the last immortal left. Does that mean Jack and Missy die ? . Don't know about any other immortals. Jack is the eternal man thanks to Rose while Missy is well Missy. If there is one thing she is good at it is surviving. So if they can't make it all the way to the " end of time". It must be something big. . However we have had this before. Doctor was suppose to die at Trenzalore twice. First time he faked it with a teselecta robot decoy. Missed oppurtunity what would the universe be like if the doctor was dead. No consequences . Second time he got a new set of regenerations. So maybe future events and timelines can be changed. Only one way to find out watch it.

Missy isn't an immortal, Jack died.

And the fact Ashildr survived when she wasn't even immune to damage is a joke.

There is no actual evidence (that we've seen so far) that Asildr actually lived all the way to the end of time and didn't just get there by Tardis in the same way that the Doctor did.

Yes she said that she had lived that long, but she is not exactly famed for her honesty.

We do know that she has been chummy with the Timelords and has hung around them (or Gallifrey) long enough to learn to read Gallifreyan (she is reading the "Diner Tardis" manual to Clara at the end of the episode).

What did me live on? I presume she had to eat. Must have got a very big shop in before everything turned to dust.

Freys.

When did Jack die ? and don't mention the Face of Bo thing because that connection hasn't been confirmed within the Who universe. Ok most of us want him to be Bo but until someone actually confirms that then it's supposition.

That is definitely what is implied, and did you see Jack at the end of the universe? I didn't.

Implied yes, but never confirmed anyway Jack might have been there, just not seen
I was never convinced that Ashildr was truly immortal like Jack. I would, like others have already said, like to know how she kept herself alive without food etc.

Maybe Ashildr is a bit like Connor and Duncan from Highlander.
Only think that could have killed her is decapitation. Guess she was just lucky and carefull not to have suffered any damage during her very long life.

Jack isn't immortal any more due to Miracle Day.

You know that got undone right?

The problem with that is that her immortality was the result of alien repair technology. If it was that simple, why isn't the end of the universe overrun with immortal Mire soldiers?

Easily explained

a) She time-travelled forward some of it, so didn't experience the whole of the billions upon billions of years to the end of the universe.

b) The Mire relied on having the reputation of an aggressive species, but were in fact, rather less than competent, at least by the time of their encounter with the Doctor. (Maybe they were truly formidable at some point in the past, but lost their edge as the generations passed). Somebody could have developed the technology to wipe them all out in the billions of years to the end of the universe. Perhaps they caught a particularly nasty and virulent disease from an unexpectedly dirty telephone? The point is, with that amount of time, almost any explanation for their absence at the end would seem plausible.

if you can produce a stable bubble in time at the end of the universe - when sub atomic particles even are vanishing into nothing , sandwiches are not a problem.

Jack changed with age.He pretty clearly does end up deteriorating physically as Boe. Rose gave him life. But she didn't necessarily give him a self repair system, and she may not have stopped the effect of the the second law of thermodynamics or the extreme physics of the big crunch, or big freeze or the other end of universe scenarios.
https://en.wikipedia.org/wiki/Ultima..._or_heat_death

Ashildr is also established as someone who learns and develops. She's smart enough to assimilate knowledge and technology, and at some stage over billions of years would have worked out how to store and retrieve data, externally to her head. She's gathered the knowledge of the universe and left the Doctor far behind. There's no reason to think Jack did that that, or was that technically interested, or capable .

Even Ashildr though can't survive right till the end- which is why she needs a Tardis to escape and regain more time again. The plot question is why she didn't develop her own Tardis? Perhaps she wanted someone to share eternity with?

No he doesn't "pretty clearly ends up as Bo" It's hinted at and implied but never actually stated. By bringing Jack back to life, Rose did make him immortal with a self repair system, just look at the first episode of Children of the Earth, having been totally blown apart, Jack's body repaired and rebuilt itself out of the atoms and molecules in the air. Now I can accept that Ashildr has been given alien tech in order to prolong her life but I bet she couldn't rebuild herself the way that Jack can.i

Ashildr is probably the most flawed character in Doctor Who period.

Amen.

All this talk of immortals, makes me ask if President Borusa is still "Alive"? All be it as living stone in the Tomb of Rassilon