[3.X] Critical Hit Injuries

[liquidformat]

So it has always bugged me that even though there are some mechanics inside 3.5 for regaining or replacing limbs there really wasn't much done on how you loose them anywhere. So I have been milling around with the idea of injuries on criticals. Here is what I have so far:

When you score a critical with a weapon you auto confirm for bonus damage. Critical confirmation roll is to determine if deal an injury. If the critical confirmation succeeded then they move to a injury table to determine the injury. If a 20 is rolled on the attack and on the critical confirmation roll, the target must make a fort save DC equal to damage modified by critical modifiers, if the target succeed the damage is increased by 1 times (so x2 now becomes x3, x3 becomes x4), if the target fails they die.

On to the injury tables, I am still working out what should be on here and how likely, here is what I have so far:

Piercing:
bleeding
gut wound (limited to partial actions take 1 con damage every x rounds)
blinded
severed artery(take 1 con damage/round)

Slashing:
bleeding
gut wound (limited to partial actions take 1 con damage every x rounds)
blinded
severed right leg (fall prone, unable to stand without a dc 30 balance check, movement speed reduced to 5' requires dc 30 jump check each round or fall prone)
severed left leg (fall prone, unable to stand without a dc 30 balance check, movement speed reduced to 5' requires dc 30 jump check each round or fall prone)
severed right hand
severed left hand
severed artery(take 1 con damage/round)

Bludgeoning:
dazed
sickened
broken right leg (fall prone, unable to stand without a dc 30 balance check, movement speed reduced to 5' requires dc 30 jump check each round or fall prone)
broken left leg (fall prone, unable to stand without a dc 30 balance check, movement speed reduced to 5' requires dc 30 jump check each round or fall prone)
broken right hand (can't use hand)
broken left hand(can't use hand)
broken ribs (limited to partial actions)
concussed (unconscious for 1d6 rounds, confused after, make a dc 40 balance check each round or fall prone)
internal bleeding (take 1 con damage/round)

broken bones can heal on there own in 6 months 50% chance of gaining a permanent deformity if not treated. With weekly heal check of 20 (or 1 casting per week of cure minor wounds) broken bones heal in 3 months with no chance of permanent deformity. With weekly heal check of 30 (or 1 casting per week of cure light wounds) broken bones heal in 2 months with no chance of permanent deformity. With weekly heal check of 40 (or 1 casting per week of cure moderate wounds) broken bones heal in 1 months with no chance of permanent deformity. With weekly heal check of 50 (or 1 casting of cure serious wounds) broken bones heal in 1 week with no chance of permanent deformity. Heal spell and Regenerate heals broken bones immediately.

Deformities can be healed only with a regenerate spell:
limp: -10 to land speed, legs only
weak: -2 str, -4 to all checks covered by endurance
stiff: -2 dex
bad blood flow: -2 con

concussed can heal naturally with 3 weeks of down time, with a dc 30 heal check (cure light/moderate wounds) with 1 week of treatment, or immediately with a cure serious wounds, heal, or regenerate spell.


Anyone tried anything like this or have some thoughts on things to add, adjust or what dice/range for each injury type?

[exelsisxax]

This does nothing to monsters, little to most NPCs of friendly disposition or nemesis, and can royally screw over the PCs. Random encounters can eat an injury and die without breaking campaigns. If a party gets attacked a couple lucky 20s can turn them into a band of cripples that used to be an adventurer like you. Do not ever do this or anything like it unless you plan on handing out some scrolls of regenerate and restoration from the get go.

[JNAProductions]

This does nothing to monsters, little to most NPCs of friendly disposition or nemesis, and can royally screw over the PCs. Random encounters can eat an injury and die without breaking campaigns. If a party gets attacked a couple lucky 20s can turn them into a band of cripples that used to be an adventurer like you. Do not ever do this or anything like it unless you plan on handing out some scrolls of regenerate and restoration from the get go.

Seconding this.

[heavyfuel]

People who are saying this will mostly affect the PCs are right. HOWEVER, that shouldn't discourage you from implementing a new mechanic. A lot of mechanics already negatively impact the PCs rather than NPCs. Save or Dies, auto hitting on a 20, level loss from raise dead and similar spells, and level adjustment, just to name a few.

Being aware that this mechanic will impact players more than NPCs is just something you must have in mind when thinking about the specifics.

I had an "injury" mechanic that came into play every time a character was dropped to -1 or lower. I put this mechanic (and others) in the game because the campaign style would rarely allow more than 1 encounter per day, so this was a way to drain resources even during downtime. They could start the day with full HP, but they'd still be suffering from last week's combat.

With this in mind, I went for small, long lasting penalties as opposed to high, short lasting ones.

Think about what you want for your game and tailor this injury mechanic to your campaign and players.

[Saintheart]

It might be worth looking at the SRD's Massive Damage Thresholds document (http://www.d20srd.org/srd/variant/adventuring/massaveDamageThresholdsAndResults.htm) when assessing Fort saves on this.


When you score a critical with a weapon you auto confirm for bonus damage. Critical confirmation roll is to determine if deal an injury. If the critical confirmation succeeded then they move to a injury table to determine the injury. If a 20 is rolled on the attack and on the critical confirmation roll, the target must make a fort save DC equal to damage modified by critical modifiers, if the target succeed the damage is increased by 1 times (so x2 now becomes x3, x3 becomes x4), if the target fails they die.

At very low levels this is I guess tolerable, but once you add magic or STR bonuses this can very quickly add up in that small set of cases where it's a 20 on the attack, 20 on the confirmation.

So just as an example, this would mean if it's a 20 on the attack roll and 20 on the confirmation roll, if the target takes a hit from a regular 1d8 20/x2 longsword wielded by a commoner with STR 10 and therefore +0 to add to the damage, that would mean the target has to roll a DC 16 Fort save or die. For comparison, 3.5's default Massive Damage rules impose a DC 15 Fort save or die if you're hit with a single blow of 50 hitpoints which doesn't kill you outright. Odds are most fighters and similar are going to be able to make that save at low-ish levels.

Arm that same STR 0 commoner with a spear, though, it's a Fort DC of 24: 1d8/x3. Same goes for arrows shot from plain, ordinary longbows.
Arm him with a scythe, and the +0 commoner is imposing a Fort DC of 32 on the fighter: 2d4/x4. By definition, the fighter can't save against that hit unless he has at least a +12 effective in his Fort save, which the fighter only gets -- natively -- at 20th level. Assume you're only going to be able to heap +5 or so on his Fort save via magic, and he still doesn't save even half of the time. I suppose epic DR might help, but I'm not sure if it counts in this situation.

And these calculations all assume regular weapons. Add magic or even a +1 to STR of any opponent and the numbers blow out even worse. AC doesn't help at all, since this scenario rests on native dice rolls, of which there's a 5% chance every time.

These are more observations on the lethality than criticisms, but it certainly would leave even Fighter 20s nervous across the campaign: the odds of 2 20s is 1 in 400, so even the highest-grade Fighter in the land with an effective Fort save of +12 and no other options can theoretically only expect to live for around 400 attack rolls before he gets the 20/20 that kills him, because even with a +12 to Fort he only reaches DC 32 5% of the time. And that's assuming a Fighter 20 taking on a commoner with a scythe. If it's a 20/20 roll, the Fighter 20 has only a 5% chance of survival. Anyone with a Fort save less than +12 - i.e. anyone other than a Fighter - it's automatic death, they literally cannot make that save. Similar odds of automatic death persist where the commoner is armed with a sword or spear if the character can't hit a DC 15 or DC 24. Under these rules, magic becomes a lot more important: Wind Walls go up everywhere to stop ranged attacks, miss chances and DR get a lot more important.

[Eldariel]

I don't think crits should multiply damage if you go with an injury system instead. Either-or. Otherwise they're just too swingy. FWIW I've done more or less the same: bypass target's AC by 10 to threaten a critical or 20 for a double critical threat (or 30 for a triple and so on). I use the "20 is treated as +30 and 1 is treated as -10" from Epic rules since it's just better. Injury system mostly is damage/weapon independent; either you take an injury or you don't. I'm still working on the details of how to exactly do called shots properly and how to properly introduce crit diversity into the system. though. Right now we're just rolling for bodypart damage for a flat set of penalties on the first crit and loss of said limb (death on a headshot) on the second one.

[Saintheart]

I don't think crits should multiply damage if you go with an injury system instead. Either-or. Otherwise they're just too swingy. FWIW I've done more or less the same: bypass target's AC by 10 to threaten a critical or 20 for a double critical threat (or 30 for a triple and so on). I use the "20 is treated as +30 and 1 is treated as -10" from Epic rules since it's just better. Injury system mostly is damage/weapon independent; either you take an injury or you don't. I'm still working on the details of how to exactly do called shots properly and how to properly introduce crit diversity into the system. though. Right now we're just rolling for bodypart damage for a flat set of penalties on the first crit and loss of said limb (death on a headshot) on the second one.

On called shots, have you considered importing 5e's concept of disadvantage on the roll into 3.5?

i.e. if you want to make a called shot for X damage for zeroing in on a body part, you roll 2d20 and have to take the lower of the two results as your attack roll? Makes for a nice tradeoff to my mind - if you want extra damage, you have to take a higher chance of a miss, but against weak or vulnerable opposition, the odds are as good as doing normal damage?

[liquidformat]

Arm that same STR 0 commoner with a spear, though, it's a Fort DC of 24: 1d8/x3. Same goes for arrows shot from plain, ordinary longbows.
Arm him with a scythe, and the +0 commoner is imposing a Fort DC of 32 on the fighter: 2d4/x4. By definition, the fighter can't save against that hit unless he has at least a +12 effective in his Fort save, which the fighter only gets -- natively -- at 20th level. Assume you're only going to be able to heap +5 or so on his Fort save via magic, and he still doesn't save even half of the time. I suppose epic DR might help, but I'm not sure if it counts in this situation.

An important thing to remember is a x4 mod means I have to roll 8d4, statistically speaking rolling 32 you has less than .01% chance, so I am ok with that being an 1 hit ko if rolled by a commoner with 10 str. You would expect to be hitting 15-25 ~90% of the time on 4d8. With that said I get your point once you start adding in power attack, str and so on crits do become quite lethal not because of the damage of weapons but because of flat adders.



I don't think crits should multiply damage if you go with an injury system instead. Either-or. Otherwise they're just too swingy. FWIW I've done more or less the same: bypass target's AC by 10 to threaten a critical or 20 for a double critical threat (or 30 for a triple and so on). I use the "20 is treated as +30 and 1 is treated as -10" from Epic rules since it's just better. Injury system mostly is damage/weapon independent; either you take an injury or you don't. I'm still working on the details of how to exactly do called shots properly and how to properly introduce crit diversity into the system. though. Right now we're just rolling for bodypart damage for a flat set of penalties on the first crit and loss of said limb (death on a headshot) on the second one.

That is actually a pretty cool way to handle criticals. The one issue I see is that type of system makes weapons like rapiers and scimitars less viable, and with a critical injury system based on crit confirmations it makes damage multipliers less important. Both systems seem to have issues.

[Saintheart]

An important thing to remember is a x4 mod means I have to roll 8d4, statistically speaking rolling 32 you has less than .01% chance, so I am ok with that being an 1 hit ko if rolled by a commoner with 10 str. You would expect to be hitting 15-25 ~90% of the time on 4d8. With that said I get your point once you start adding in power attack, str and so on crits do become quite lethal not because of the damage of weapons but because of flat adders.

Huh - I must have somehow read "max damage" for bonus damage in the phrase. My mistake.


That is actually a pretty cool way to handle criticals. The one issue I see is that type of system makes weapons like rapiers and scimitars less viable, and with a critical injury system based on crit confirmations it makes damage multipliers less important. Both systems seem to have issues.

In order to do very significant things with criticals in 3.5 you generally need both a multiplier and a better threat range, but absent seriously optimised play, I'd argue it's easier and more pragmatic to have a larger threat range than it does a larger damage multiplier. Getting to x5 multipliers usually takes Kaorti Resin shenanigans or situational PrCs, but getting a critical threat range of 15-20 is pretty easy with a feat or a keen scimitar. As to how the damage plays out: back in the suggestions thread for PhantasyPen's Critfishing Handbook (http://www.giantitp.com/forums/showthread.php?569020-Fishing-Ideas-for-the-Crit-Fishing-Handbook/page4), Maat Mons did a mathematical calculation of how much bonus damage can be expected from critical hits. His working was as follows:


To get the % increase, we need to take (a - b) / b, where a is the damage with critical hits, and b is the damage without.

So, to involve way too much math, we're going to define the following variables:
Phit = probability that attack roll is high enough to hit target's AC
Pthreat = probability that attack roll is within weapon's critical threat range
D = weapon damage before critical multipliers
M = critical multiplier

So, what's the expected value for damage against crit-immune enemies? That's pretty straightforward.
Phit * D
That's the probability that we hit, times the damage we deal if we hit
That's our b from (a - b) / b.

What's the expected value for damage against enemies that are subject to critical hits? Slightly more complicated.
It's the odds that we critically hit times the damage of a critical hit, plus the odds of a non-critical hit times the damage of a non-critical hit.

The critical hit part of that is pretty straightforward. Assuming that any roll good enough to be a critical threat is also good enough to hit, it's
Pthreat * Phit * D * M

There are two ways of getting a non-critical hit. We can roll a critical threat and fail to confirm, or we can roll a hit that wasn't a high enough roll to be a threat. So the odds of a non-critical hit is the sum of the odds of those two events.
Pthreat * (1 - Phit) + Phit - Pthreat
And then of course multiply by non-critical damage, D.

So the big, complicated formula becomes:
[ Pthreat * Phit * D * M + (Pthreat * (1 - Phit) + Phit - Pthreat) * D - Phit * D ] / Phit * D
Which, when you cancel out the terms, becomes the much friendlier-looking formula:
Pthreat * (M - 1)

So, and this is an important result, once both the initial attack roll and the critical confirmation roll are both factored in, they both factor out.

As such, we can very easily calculate the value of the critical threat range/multiplier of weapons:
x3: +10% damage
19-20/x2: +10% damage
x4: +15% damage
18-20/x2: +15% damage
19-20/x3: +20% damage
17-20/x2: +20% damage
19-20/x4: +30% damage
15-20/x2: +30% damage

I tabulated the results based on those calculations, which comes out like this:




Threat Range
x2
x3
x4
x5
x6
x7
x8


20
+5%
+10%
+15%
+20%
+25%
+30%
+35%


19-20
+10%
+20%
+30%
+40%
+50%
+60%
+70%


18-20
+15%
+30%
+45%
+60%
+75%
+90%
+105%


17-20
+20%
+40%
+60%
+80%
+100%
+120%
+140%



16-20
+25%
+50%
+75%
+100%
+125%
+150%
+175%



15-20
+30%
+60%
+90%
+120%
+150%
+180%
+210%



14-20
+35%
+70%
+105%
+140%
+175%
+210%
+245%


13-20
+40%
+80%
+120%
+160%
+200%
+240%
+280%


12-20
+45%
+90%
+135%
+180%
+225%
+270%
+315%


11-20
+50%
+100%
+150%
+200%
+250%
+300%
+350%


10-20
+55%
+110%
+165%
+220%
+275%
+330%
+385%


9-20
+60%
+120%
+180%
+240%
+300%
+360%
+420%


8-20
+65%
+130%
+195%
+260%
+325%
+390%
+455%


7-20
+70%
+140%
+210%
+280%
+350%
+420%
+490%


6-20
+75%
+150%
+225%
+300%
+375%
+450%
+525%


5-20
+80%
+160%
+240%
+320%
+400%
+480%
+560%


4-20
+85%
+170%
+255%
+340%
+425%
+510%
+595%


3-20
+90%
+180%
+270%
+360%
+450%
+540%
+630%


2-20
+95%
+190%
+285%
+380%
+475%
+570%
+665%



As said, it looks like you get a lot more bang for your buck pushing the critical threat range as a priority and then applying multipliers, because it's harder to climb from a x4 multiplier to a x5 than it is to climb from 18-20 to 15-20. Get a keen scimitar, and there's your 15-20 threat range. Make it a kaorti resin weapon and your expected damage bonus rises by 60%. (in the transit from x2 to x4, remembering that kaorti resin is an increase to x4, not an increase in multiplier based on the weapon involved.) By contrast, if you've got a 20/x2 longsword and make it a kaorti resin weapon, the increase is only 10% because the threat range is much lower.

[skunk3]

There is a third-party book called the "Critonomicon" that deals with this sort of stuff in lots of interesting ways.

[Saintheart]

On a more philosophical note, I'd actually look at asking myself this question: what is my intent in changing the rules around this subject, and what purpose will changing it in this manner actually achieve?

I get that there's a lot of wonky rules in 3.5, but I'd argue by itself that's not a reason to change a large system. At least the wonky rules are there and you can account for them or seek advice on how to account for them or flat out just not use them at all. Altering a mechanic you have to consider what your purpose is in doing so and how that purpose is going to play out in terms of the players receiving it and how they respond to it in game terms.

Is the intent to make combat more interesting? Fair enough, I find "Good to go if I'm above 0" a bit of an unsatisfying way to simulate combat at times too. And I am a very latecoming fan of ability damage via an ongoing disease, having had it smacked on me at low-ish levels without ready access to clerical magic to cure the disease - I judge the fact it makes me grind my teeth as a player in a good way as a sign that it works. It's a real limitation ... provided there's not much magic to counter it. I'm just saying that you might need to take account of the fact that imposing injuries on criticals is likely to push people even more towards magic options to fix it.

I also wonder about going heavily simulationist. I'm thinking of those severed artery results or severed legs. While a person theoretically bleeds out in five minutes, if you're in heart-pumping combat or the injuries are severe, the blood loss is much faster and death approaches much more rapidly. CON damage means a person with a severed artery can still fight on at full strength for another 10 rounds. And fair enough, there is some arbitrariness inherent in all game mechanics, but the moment you start going with injury results the armchair physicians at the table start objecting about how the stats reflect physical reality. That might or might not be a good thing, maybe you want a system where if a person does suffer a severed arm then if some quick-thinking and cruel fellow PC immediately casts a Heat Metal on his weapon and cauterises the wound that mitigates or stops the damage caused, but I'm just saying linking major injuries like that to criticals is going to invite players to object or try and come up with real-world ways to get around what is a mathematical gimp on a character's stats.

Here's a thought: don't assign names to the different injuries, but to simply say "If you crit, you do damage to an ability stat, to reflect the fact you've really hit them a good blow of some kind that cripples them at least for the remainder of this combat. You knock -6 off one of your target's stats -- player's choice." The reason you give the player a choice is that since you've taken away the momentary thrill of them doing a big wad of extra damage against the stat that brings them closer to ending the fight, and since you're not giving a simulationist injury where they can track how long before the opponent bleeds out, you have to replace it with something. So you've given the player the thrill of an option, a choice: smack the opponent's attack rolls, defence rolls, hitpoints, or casting stats ... and by extension one of the opponent's saving throws too depending which stat they pick. Indeed if one stat is low enough, it'll render the opponent helpless or dead. Against casters it's a handy debuff because it may well knock a couple of their higher-level remaining spells out too.

And the best part of that approach? It leaves the player to speculate about what he's doing to the opposition. "I swing and crit and break the guy's arm. He won't be using that damn mace anywhere near as much now." And the combat stats from then on will reflect it, because you nerfed his attack roll by 3 and his damage rolls by 3.

[Clementx]

If you want maiming, you need to restrict it to something more momentous than an enemy rolling a couple high numbers, especially if they are significant penalties.

You are right that there is no real way to cripple. I give the option on a Coup de Grace of blinding, deafening, amputation, or dealing 1d6 ability drain rather than death on a failed save. Works for torture, and enemies who would take the time in a fight are probably sadistic enough to prefer it to quick death.

If you want injuries to come about naturally, model them after diseases. Fort save after exposure=injurous event. Ability damage that reoccurs, competing with natural recovery until a few lucky saves in a row=natural recovery, or heal checks/more specialised magic than CLW.