Westeros is a violent place, which is why every season of "Game of Thrones" features an astonishing breadth and variety of injuries, diseases, and deaths.

But as we discovered in the first installment of our popular "A Doctor Explains" series (Read Part 1 and Part 2), some of these deaths are medically accurate, and some are a bunch of hooey. And this week, MTV News caught up once again with surgeon and trauma expert Dr. Deborah Mogelof to get an informed opinion on some of the shootings, stranglings, and various other indignities we've seen characters suffer in Seasons 4 and 5. (Interview has been condensed and edited.)

Joffrey Baratheon: Poisoned at the Purple Wedding

Since our expert doesn't watch "Game of Thrones," we sent her a video of the Purple Wedding's climactic scene, explained the circumstances, and asked if there was any real-life poison that would cause such a spectacular (and messy) death.

Dr. Mogelof: I think the closest thing we have is arsenic. That's also a powder, and it does cause a profound gastroenteritis, so you can hemorrhage like that.

MTV News: And is it as fast-acting as we see here?

Dr. Mogelof: If you gave him enough, it would be within minutes, yes.

MTV: And as far as an antidote…

Dr. Mogelof: There is a treatment for arsenic poisoning, a compound that binds to the arsenic and takes it away. But in that moment, no. There's nothing that could have been done for him.

In summary: Ding-dong, the Joffrey is dead — and it's entirely realistic, right down to the blood and vomit spewing out of his nose. Hooray!

Bronn: Surreptitiously scratched with a poison blade, survived to be elbowed in the face by Areo Hotah

A sneaky poison that takes hours to take effect: Is it fact, or fiction?

MTV: This sort of slow-acting poison is obviously used as a plot device pretty often, but does anything like this actually exist?

Dr. Mogelof: It's definitely nothing that I'd ever been exposed to in any of my training, but the thing I discovered, which it sounds like, is curare. It was used in Central and South America, they would put it on the tips of arrows. And if you get it into, say, the carotid vein, that would cause death within minutes. But if you get it into the muscle, it could take a few hours, depending on how deep into the muscle it went and how much poison there was.

MTV: What's actually happening in the body as the poison begins to take effect?

Dr. Mogelof: It causes paralysis of your skeletal muscle. So eventually people would asphyxiate, because their diaphragm isn't moving.

MTV: And how about the antidote? On the show, it takes effect immediately, which seems unrealistic.

Dr. Mogelof: There is an antidote, which is a cholinesterase inhibitor. And it would depend on the situation; if someone came in with a blow dart to their carotid, I don't think there would be anything we could do for them.

MTV: But if you'd gotten scratched on your bicep, say…

Dr. Mogelof: Yes, it would take effect pretty quickly.

In summary: Bronn's poisoning and subsequent survival is totally on the mark, and what seemed like a totally outlandish plotline is one of the more medically accurate moments on the show.

The Stone Men: Worst. Rash. EVER.

Is there actually a real-life counterpart to the mysterious "greyscale," which turns ordinary humans into scaley, ossified, homicidal lunatics?

Dr. Mogelof: There is a real disorder called fibrodysplasia ossificans progressiva, and its lay term is "stone man syndrome." It causes fibrous tissue to ossify, so it turns to bone.

MTV: What's weird is that in this case, although they're called stone men, the thing that's actually afflicting them is more of a skin condition — like scales, or maybe terrible warts.

Dr. Mogelof: Oh, syphilis can often look like that! If you've seen old photos of people who had it, they do begin to look deformed.

MTV: But would syphilis make you crazy?

Dr. Mogelof: Actually, in and of itself, syphilis can make people… well, crazy, yeah. You'll see neurological effects, as well as mental disorders.

In summary: Not only are there diseases out there that will make you both scaley *and* maniacal, but it's legitimately possible that the Stone Men are just suffering from a rampant, untreated STD.

The Hound: Beaten by Brienne, left for dead by Arya

Poor Sandor Clegane was already suffering from a possibly-infected neck wound when he got his butt kicked by Brienne, but it was definitely the pounding (and long tumble down a rocky cliff) that did him in. Could he have been saved?

Dr. Mogelof: In this case, we're looking at traumatic brain injury, and maybe internal bleeding, but it's likely the brain injury that will kill you.

MTV: What are the effects of a brain injury? This guy is still pretty lucid as he's dying.

Dr. Mogelof: Being lucid actually doesn't mean you cann't have a head injury. If you have a subdural hematoma, you'll have a lucid interval; people seem fine, and then they deteriorate as the hematoma gets bigger in their brain. You could also have a massive organ bleeding, or a blood vessel ruptured and bleeding. Then you'll lose the blood pressure to the brain.

MTV: So if he has internal injuries, internal bleeding, it's actually the loss of blood pressure that would ultimately kill him.

Dr. Mogelof: That's right.

MTV: And if it's a brain injury, a subdural hematoma, what's happening there?

Dr. Mogelof: There's an accumulation of blood, either inside the brain itself or just inside the skull. As this hematoma gets larger, it starts to compress different brain structures that you need to breathe, and so on. Without that pressure being relieved, you'll just deteriorate, become unconscious, stop breathing.

In summary: The Hound was right on the money when he said, "Unless there's a maester hiding behind that rock, I'm done." (And while he didn't croak onscreen, unless there was a maester hiding behind that rock, he's definitely dead.)

Shae: Strangulation-by-necklace

Shae's roll in the hay with Tywin ended with her death. How would she have fared in real life?

MTV: For starters, I assume that once you've been strangled, there's no coming back from that.

Dr. Mogelof: I've only had one case like this, where a man tried to hang himself, and it was awful. We couldn't do anything for him. So, dying from strangulation is similar to a hanging, but instead of your bodyweight compressing everything, it's the other person, and it depends on whether they're pulling up, or pulling backward. There are several things that can happen: You can die from compression on your carotid artery, which causes ischemia to your brain — no blood flow. Or you can die if they crush your larynx, because you can't breath anymore.

And then there's something called the carotid sinus reflex. It's kind of a dilated area in your internal carotid, and if someone puts enough pressure there then your heart rate slows, your blood pressure goes down, and you eventually go into cardiac arrest.

MTV: That last one sounds like a ninja sort of thing, or like a Vulcan nerve pinch.

Dr. Mogelof: It's very rare. You have to hit exactly the right spot for that.

MTV: So unless they actually crush your larynx, it's the loss of blood flow to the brain that kills you, and not being unable to breathe.

Dr. Mogelof: That's right.

MTV: So how long would you have to strangle someone — like, if you were to start strangling someone, but stopped before they were dead, would they be able to come back from that?

Dr. Mogelof: It would depend on how long they were unconscious, and how much ischemia was there. It's like with a drowning victim — you might be able to bring them back, but they're braindead. If it's been a short enough period of time, with enough blood flow, you could come back, although you might not be 100% with all your faculties.

MTV: So all these scenes in movies, where someone is choked out, and they pass out, but they recover completely later on — is that realistic?

Dr. Mogelof: If it's not too long. Or if they do the carotid thymus reflex, and the victim's heart rate just went so low that he passed out, and then they let go, he'd be fine.

MTV: And if your larynx was crushed, and someone found you in that condition, would they be able to do anything for you?

Dr. Mogelof: They'd have to perform an emergency tracheotomy. Otherwise, you would asphyxiate.

In summary: The act of being strangled would have rendered Shae unconscious in less than 30 seconds, but considering that Tyrion only hung onto the chain around her neck for 30 seconds total, her odds of survival weren't all that bad. In real life, she might still be alive and well and looking for someone else's life to ruin!

Tywin Lannister: Shot with an arrow on the john.

As it turns out, this dramatic death scene would have been a tad bit different in the real world.

Dr. Mogelof: Remind me, where does he get shot?

MTV: [Resisting the urge to yell, "ON THE TOILET!"] The first arrow goes in under his left pec. The second hits him in the shoulder.

Dr. Mogelof: So the way an arrow works, it's constructed to rotate, which causes it to travel more efficiently in a horizontal plane and then also cause more damage when it hits someone.

MTV: So it sort of burrows in upon impact.

Dr. Mogelof: Exactly. And the quickest way to kill someone with an arrow is to get it into the thoracic cavity, either heart or lungs. In this case, it would be the lungs. You can get a pneumothorax, or a hemopneumothorax, where you puncture the lung, the lung collapses. Then the air fills up outside the lung, and crushes the lung. But you can fix it if you take a needle, and puncture the chest wall to allow the air to come out, and put in a chest tube. Then the lung will inflate again.

MTV: Obviously that didn't happen on "Game of Thrones," because Tywin died, but there's actually a scene in the new "Mad Max" movie where somebody does that. It's excruciatingly painful, right?

Dr. Mogelof: It's awful. It's awful. These guys will come in to the ER who have been shot — they're gang members, covered in tattoos — and they can't handle it. You're awake, and you feel everything.

MTV: So if someone had found Tywin, and punctured his chest, and put in a tube, his lung would reinflate.

Dr. Mogelof: Yes.

MTV: What about the arrow?

Dr. Mogelof: Well, yeah. You'd have to take the arrow out.

MTV: What would the best way be to do that? Just, like, yank it?

Dr. Mogelof: Well, in a hospital setting, it would be first the needle decompression, then the chest tube, then you'd take them to the OR to remove the arrow. But… yes. Just yank it.

MTV: And if you don't do this...

Dr. Mogelof: They'll asphyxiate. It would be a matter of minutes, when the whole lung is collapsed.

MTV: Speaking of, would you still be able to talk under those circumstances? Like, deliver a dramatic monologue cursing the other guy for shooting you?

Dr. Mogelof: No, I don't think so. You'd be gasping for air, you couldn't speak.

In summary: In real life, Tywin's injuries would have not only killed him without intervention, but also made it impossible for him to deliver that super-mean "You are no son of mine" speech in his final moments.

Shireen Baratheon: Burned at the stake.

Would Shireen's death have been as ghastly and prolonged in real life as it was on the most recent episode of "Game of Thrones"?

Dr. Mogelof: People who die by burning don't usually burn to death. The smoke inhalation would make you pass out, and kill you, before anything else. It's also possible to die from loss of fluids -- open wounds, sweating, blood. Or you can get carbon monoxide poisoning from the fire.

MTV: This death scene went on for ages and involved a lot of screaming. Would a person being burned at the stake in real life remain conscious for so long?

Dr. Mogelof: It's unlikely. People die in fires all the time, from smoke inhalation, and it just doesn't take that long before you're overcome.

MTV: And if you were going to somehow survive, how long could you be engulfed in flames and still make it out alive?

Dr. Mogelof: If you can withstand and stay awake -- if the pain itself doesn't make you pass out -- you'd probably have a few minutes.

In summary: Poor Shireen never had a chance, basically. But in real life, her end would have been much more mercifully quick, so there's that.

Oberyn Martell: You know how he died. Don't make us say it.

After a lengthy discussion of the most horrible scene ever to take place on "Game of Thrones" (which I watched repeatedly so that our medical expert didn't have to), we came to a conclusion that actually might make you feel a whole lot better about it.

Dr. Mogelof: Honestly, I don't know if any human being could actually do that to someone. He literally just puts his hands on either side of the head and squeezes?

MTV: I'm going to have to watch it again. Let's see, he's got his thumbs in his eye sockets, and there's blood squirting out everywhere, and then— AUUUUUUGH — there's a cut-away, and a huge spray of blood, and then they cut back and his head is just… splattered. So just for starters, with the thumbs in the eyes, would there be this explosion of blood?

Dr. Mogelof: Yeah, there's the retinal artery back there. So, yes.

MTV: But the actual head-splattering—

Dr. Mogelof: I don't think anyone could actually apply enough pressure to make that happen. A really strong person could maybe give someone a horrible brain injury, somehow, but I can't imagine crushing the skull completely.

MTV: What if the killer leverages his own bodyweight to apply pressure from above, pushing the victim's head against the ground? This guy must weigh about 400 pounds — what if he's pushing down from above, using all his weight?

Dr. Mogelof: Well, to fracture the skull requires 500 kilograms of force. And a man who weighed 500 kilograms would be 1,000 pounds, so...

MTV: Oh so that's quite unrealistic.

Dr. Mogelof: Yes.

MTV: So in real life, Oberyn Martell would have never actually died this way.

Dr. Mogelof: No.

MTV: This is going to sound really weird, but that's actually incredibly comforting.

In summary: In real life, the wonderful, beautiful Oberyn Martell would still have his perfect skull intact… although he'd still be eyeless, toothless, and probably just as dead from a traumatic brain injury. *Sob.*