There are as many ancient ones as there are parallel universes, just as there are as many Dr. Stranges as there are yada yada yada. That's the whole point!

So why would the rest of the multiverse care that this particular one died?

Because, according to how the multiverse works, what happens in one universe affects other universes.

In what way? Assuming there are an infinite number of universes wouldn't there be just as many universes in which she/he survived as died?

Dr. Strange, it turns out, is as powerful as Thanos with all infinity stones in the gauntlet - both can destroy entire universes through their actions (one only has to snap his fingers while the other has to commit a blunder that has ripple effects).

They – wielder of the "Infinity Gauntlet" – cannot "destroy entire universes", just alter (e.g. destroy) much of or all the contents (e.g. living sentients) of a "universe". Apparently, there is only one "Infinity Gauntlet" in the "multiverse" or maybe that each universe in the multiverse has its own "Infinity Gauntlet" that only affects that one universe and not any of the others.

NB: Btw, besides Silver Surfer & Vision, my favorite Marvel character since the early 1970s has been Doctor Strange. I have no idea, however, what they've done with either of them in the last forty or so years (the MCU doesn't count in my book) :nerd:

I win on a technicality though 180 Proof - altering the contents of a universe at will and in any way one fancies is to have an effect on the entire universe. Me getting all nerdy here.

I like Dr. Stephen Strange too, but it's odd that someone like yourself - dead against magical thinking - should have him on your list of favorite (Marvel) character. Does this mean, mon ami, that there's a place in your heart for religious folks? :grin:

I was about 8 years old and an altar boy attending a Catholic grammar school when I became a Doctor Strange fan. Dinosaurs, mythologies & Star Trek, along with Marvel comics, were my jam back then. I don't think "magical thinking" in any literal sense (e.g. religious or occult) ever had anything to do with my pop-culture preferences as a kid.

Hey Strange, you know what's cooler than magic? Math! — Spider man

Peter Parker says the above line while inside Dr. Strange's illusion - it so happens that Strange's magic, it's mathematical (e.g. transformation, projection, symmetry, all mathematical (geometric) concepts). The difference between Parker and Strange is that the former understands the magic, while the latter only uses it, kinda like the difference between a automobile engineer and a driver.

Nope.

Why?

Really? :smirk: Well, off the top ... Dr. Stephen Strange's day job was "world-class neurosurgeon" (almost genius-level) which means a good deal of applied mathematics in his scientific and medical education. Peter Parker, a high school "science prodigy" didn't remotely have Dr. Strange's advanced education. Neither of them was depicted as an expert in pure mathematics but it seems to me that a scientifically well-educated "Master of the Mystic Arts" (and later "Sorcerer Supreme"), especially using the "Eye of Agamotto" so frequently, would have acquired far more insight into the Platonic domains of the most arcane mathematics than Peter Parker (Tony Stark or Reed Richards) ever dreamed of or or needed to know. In the Marvel universe, Agent Smith, magic is just sufficiently advanced math (re: the "Cthulhu Mythos" ... which, IIRC, had inspired Steve Ditko in the first place.) :nerd:

:cool:

That's what I was getting at, but medicine, including neurosurgery, doesn't really require that much math. Peter Parker was a high schoolie but he is competent enough to comment and correct the work of Dr. Otto Octavius who was this close :ok: to a breakthrough in cold fusion. So yeah.

Performing neurosurgery probably doesn't require much math but premed, medical school, pharmacology and computer imaging tech are impossible to master to a "world-class level" without mastering quite a bit of varied applied mathematics (re: graduate-level physics, organic & inorganic chemistry, molecular biology, computer programming, laboratory experimental modelling, etc). Amplified by cosmic-level arcane understanding and force-multiplied by the "Eye / Orb of Agamotto", Strange's insights into reality (mathematical and otherwise) have to be literally otherworldly or multiversal – godlike. :fire:

C'mon, dude! A teen genius "web-slinging wallcrawler's" knowledge is, at best, Earth-bound and, compared to the "Sorcerer Supreme's" comprehension, extremely parochial, even
primitive :point:

Doctor Strange : Spiderman :: Monolith : HAL 9000.

:grin:

But was there anything special about the ancient one in this main universe we follow? Or could a universe that is identical except that the ancient one survived just as significant? Why would any particular one in an infinite number of universes that rarely interact matter that much?

In the "what if..." series they covered Infinity stones only working in their particular universe. And of course in Loki at the TVA they are all powerless there. They also brought back the ancient one in some type of "echo" form.

So far I think only in Deadpool 2 did they represent an afterlife in the MCU.

As a rule, scifi / fantasy depictions of "the multiverse", like "time-travel", never make sense as they are only plot devices which don't need to.