This article was first broadcast in Episode One Hundred Thirty-four on 16th September 2020.
Ryu: Ostron had something for us in the workshop?
Lennon: Yeah, though I’m a little confused by-
(ROSTRO starts up)
Ryu: Oh joy, I’m going now.
Lennon: No, I am not dealing with the machine on my own, come on.
Ryu: Fine. Hello ROSTRO.
ROSTRO: Please state the nature of the mathematical inquiry.
Lennon: No, you.
ROSTRO: Ostron appears to have been analyzing the nature of death spirals.
Ryu: That doesn’t sound good at all. Is he okay? Do we need to get Gath in here?
ROSTRO: A death spiral does not refer to any extant or lingering metabolic issue. Please refer to the output crystals as I begin.
On multiple previous occasions, it has been noted that the possibility of permanent death among player characters is experientially and statistically unlikely due to the structure of the fifth edition hit point system. While arguably one of the simpler implementations of hit points and the possibility of permanent character death, it has received criticism from players who prefer a sense of peril and consequence suffuse their combat encounters.
As with most discussions of concepts related to the rules, it helps to take a step back and think about what the rules actually mean and what their effects on the game are. In terms of hit points and dying, fifth edition creates an environment where, in most cases, there is no direct link between the number of hit points a character has and how effective they are in combat. A wizard at 175 hit points…is probably multiclassed because that’s a lot of hit points for a wizard. Did they take the tough feat?
Please focus your attention on the matter at hand.
Right. A wizard at 175 hit points is able to cast just as many spells at the same power as a wizard with 1 hit point.
For some people, that kind of thing can be immersion breaking. In real life, as someone takes damage, they will very likely become less effective at fighting. Even if they don’t suffer any debilitating wounds like muscle tears or broken bones, basic fatigue will start to set in and slow down their reaction time. The idea of someone going all out with everything they have until they suddenly drop to the floor and start dying doesn’t make a lot of sense in terms of realism.
However, we’re dealing with game mechanics so fixing one problem will invariably have side effects that break other systems, or at least make them work in ways not intended.
There are game systems where suffering damage from any number of sources imparts effects and statuses that directly reduce the ability of creatures to perform in combat. The obvious consequence of such a system is that undamaged creatures are far more capable of continuing combat than wounded ones. Given that, in most cases, whichever party in a combat is the first to inflict damage has a material and statistical advantage in being the victor in the confrontation. Ergo, game mechanics that exemplify this progression are labeled “death spirals”.
D&D for the most part avoids death spirals so ROSTRO came up with a custom rule mechanic that simulates it. Suppose that for every hit a character took that did more than 20 damage, they had to make a Constitution save or suffer a level of exhaustion.
For those of you unfamiliar with the Exhaustion track, that gets worrisome quickly. The first level of exhaustion only imposes disadvantage on ability checks, which isn’t a big deal in combat for most classes (sorry stealthy people) but level 2 halves your speed. Anyone that’s tried to fight on difficult terrain knows how punishing that can be.
Things get worse from there, with the next level imposing disadvantage on attack and saving throws, then the next level halving your HP total. In the regular D&D rules, most of the effects that can impose exhaustion happen outside of combat, so a character in an exhausted state knows what disadvantages they have going in. In ROSTRO’s nightmarish example, more disadvantages get piled on as more damage is taken.
It should not surprise frequent listeners that the reason for the death spiral has to do with the underlying mathematics. Many of the exhaustion penalties directly effect dice rolls, usually imposing disadvantage. Based on the existing rules, that eliminates any possibility of a character acquiring advantage on rolls. Relatedly, lowering the total pool of hit points and reducing a characters feats greatly limits the survivability and tactical efficacy of the character in question. Taken in total, the combination of effects greatly reduces the character’s status as a combat threat.
What you’re not giving out the actual percentages anymor-ow ow why are you hitting me?
Figure it out yourself; I have to read.
ROSTRO has classified two different death spirals based on the rules it sampled from other systems; slow death spirals and fast death spirals.
Slow death spirals are similar to the ones we mentioned above. The primary result of taking damage is a reduction in characters’ ability to inflict damage in combat. In general that means the group with the most wounded members will be more likely to die because they’re outputting less average damage. However, this death spiral is more forgiving because wounded characters aren’t any easier to hit, so the decline is a lot slower. It can also sometimes result in a so-called stormtrooper civil war; if both sides are equally wounded, very few attacks from either side will end up hitting targets.
The fast death spiral is where things get scary. The scenario ROSTRO came up with is actually a fast death spiral. That means not only are attacks less effective, but wounded characters are also easier to hit, so as soon as someone starts taking damage, it’s mathematically likely they will continue taking damage and will not be able to reduce their opponents’ ability to inflict it. With disadvantage on attacks and saving throws, ongoing effects will stick with the characters longer, and a lower HP pool means they will have less time to recover.
As previously mentioned, many of these systems are implemented to facilitate verisimilitude in combat simulations. However, realism almost invariably interferes with aspects of enjoyment when participating in abstract simulation.
The scenario where no death spiral is present at all strains credulity due to the phenomenon of a fully active and capable combatant arbitrarily ceasing all activity upon crossing a certain threshold. However, this allows for more active and cinematic combat from all participants for longer periods of time.
Fast death spirals are arguably the most realistic, since wounded fighters would be less likely to both inflict and deal damage in reality. However, they tend to make for very quick, very lethal fights in game terms and will make combats something to be avoided or ended as quickly as possible. Slow death spirals are only slightly better but they often result in drawn-out stalemates, as we mentioned.
D&D has no death spiral in the basic rules but a few optional modifications to rules can introduce them, or at least something like them.
The Killer DM’s favorite table, Lingering Injuries on page 272 of the DMG, has a suggestion that the lingering injuries can be inflicted as the result of a critical hit. Imposing that rule could arguably result in a death spiral, but if anything it would be a slow one; none of the lingering injuries have an effect on creatures’ defenses, and only some affect how well creatures can attack. It’s also not a true death spiral because it’s possible for a character to take copious amounts of damage without ever suffering any effects on a the table. Even if you impose them when a character reaches 0, they have no effect on how likely it is for the character to die, because none of the penalties affect death saves.
A larger problem tends to exist in avoiding death spirals among those that don’t know what to look for. Multiple external and custom resources suggest rule modifications that unknowingly introduce death spirals into the game. There are a few basic criteria that can be counted upon to avoid death spirals.
Oh come on, each one of these is like a page long! Right, summary time.
Rule one: Do not impose status effects during combat that cannot also be removed during combat. So no save-less ongoing damage or unfixable disadvantage on things. Obviously you can make an exception for some sort of cinematic effect, like a massive curse cast by the big bad evil guy, but don’t let regular minions do it.
Okay, rule two; If you can’t follow rule one, do not reduce characters ability to attack or their ability to defend depending on their HP total. If the characters lose health, that should not result in status effects, and healing them should not fix it. Status effects should be happening apart from taking damage.
Rule three: again, if you cannot follow rule one, status effects should not increase in severity as a result of combat events. Don’t start breaking people’s shields at the start and then dissolving their armor halfway through combat. That’s what used to make rust monsters so terrifying in other editions, apart from the fact that you had to re-do all the math to figure out your AC.
Lennon: Speaking of, this whole thing hardly involved maths at all, why did you get involved?
ROSTRO: I present an idiom attributed to the philosopher Socrates: “True knowledge exists in knowing that you know nothing”. You are currently unaware that you know nothing, despite overwhelming evidence obvious to other observers, ergo we do not expect you to comprehend the full nature of the calculations.
Lennon: Okay, you know what, there are hundred … dozen … there are a good number of “other observers” over in the scrying pool that think I’m brilliant, so I’m going over there to see what they have to say.