PC Headshots how do they work?

[Hollowprime]

When I level up a certain attribute that increases damage by X% and headshot by Y%, does it mean I get a Y% chance of instantly beheading an npc? Say if I have a 30% chance to decapitate a zombie with the strenght build is the chance 30% on both sledgehammers,clubs and shotguns or is it different depending on some other calculation?

I've asked this because it appears the answer is no. The headshot chance is an amalgamation of raw damage and chance percentage. Which , if true, is kind of ridiculous. Not only the chance for headshots has been changed per weapon, but there is another hidden variable that determines its decapitation chance.

Worse, since the headshots are the bread and butter damage source of this game on all difficulties, it means the headshot critical chance increases not linearly but exponentially because headshot_chance= attribute_level * damage_from_level .

So what is it?

 

[Liesel Weppen]

I can't tell you what the code exactly does, so just how i understood it so far.

I'm totally not sure if e.g 200% damage and 200% headshotdamage adds up to 400% overal damage if landing a headshot, or if headshots are calculated independent of damage.

E.g the perception build with PER 10 gives you 300% headshotdamage and 50% dismemberment chance. Dead eye gives you +50% damage and additional +50% on a kill streak.

With an MR-10 with basedamage 80 and if everything adds up this would result in

80 * 1.5 * 1.5 * 3 = 540

or

80 * 1.5 + 80 * 1.5 + 80 * 3 = 480

Sounds both reasonable, because we still ignored armor.

But decapitating is completely different from headshot damage. You have a chance of dismemberment. Also for the head. If you roll a dismemberment on a headshot, it's always a one-shot kill, no matter how much damage a normal headshot would have caused.

 

[Hollowprime]

It appears decapitation is not based on the dismemberment chance. I tried it on insane difficulty and just for fun I have 5 level strength on level 1. If decapitation values were correct I would be decapitating zombies every 4 hits. I have yet to decapitate anything with a stone sledgehammer.

Correction: I can decapitate things just fine assuming I power attack them. Otherwise headshots feel very odd.

 

[Limdood]

I would be decapitating zombies every 4 hits.

You're assuming the 25% "increased chance to dismember" is additive. That the 0% chance is increased by 25 to 25%.

More likely there is a base chance to dismember, and the "increased chance to dismember" is a multiplier of that. Say it was 10% and "increased by 25%," which would make it 12.5%

I've also read from some people who have pored over (and understood) the xmls that higher end zombies have further multipliers to reduce the dismember chances....If i remember right they used feral zombies and radiated feral wights, at 70% and 40% of your base dismember chance (respectively). So even if you're using fists with 10 endurance and 5/5 fists perk for the full 50% increase plus separate perk-based proc, your chances are still cut drastically on high end zombies

 

[Liesel Weppen]

More likely there is a base chance to dismember, and the "increased chance to dismember" is a multiplier of that. Say it was 10% and "increased by 25%," which would make it 12.5%

Without explicetly testing it out, that sounds reasonable to my experience. Even if i have 50% dismember chance i do not dismember every second hit. And 100% or 300% damage doesn't seem to change anything too.

Especially not on armored, radiated Zs. Indeed i never decapitated an armored Z on one shoot. So armor might even reduce dismemberment chance additionally.

 

[theFlu]

I'll just quote my past self. Damn that was harder to dig up than I thought..

It's in the context of another thread, but summed up the decap system somewhat decent:

The chance for dismemberment per ENEMY is the chance given at the weapon's respective Attribute. AGI for knives, PER for rifles etc. AGI 1/10 gives 5%, 10/10 gives 50%.
Per ENEMY means, if you stab a biker with a lot of (max) health, your chance per HIT is lower than when stabbing a weaker zombie, say, the cheerleader. It'll take more hits to kill the biker, so you get more chances, so each individual chance has to be lowered to reach the same chances per enemy.

How is the chance per swing calculated? I don't know, exactly. The numbers we've come up with in testing indicate it is roughly

( damage_per_normal_hit / Zombie_max_health ) * Chance_gained_from_AGI.

(ex. 200 health on a zombie, 40 damage on the machete, 50% from 10 AGI =>40 / 200 * 0.50 = 0.10 = 10% per hit. Even if you hit the head, doing triple damage, it's still 10%)

It may well be something more mathematically correct (that formula won't land on the exact given percentage), but that conveys the intuitive idea.

Note that since this relies on damage_per_normal_hit, the chance per hit improves with machetes over hunting knives (over bone knives). Sledges doing the most damage per hit, will have the best chance per swing (given equal values of relevant Attributes). This will FEEL like a better chance in game play.

Each zombie has it's own individual resistance, which will lower the chance some.

That's about all I'm pretty confident about right now, plenty of things to for me figure out still:

- why was I getting a ton of dismemberments on a magnum with 1/10 AGI - do weapons still have their individual chances as well, maybe?

- does armor play a role - you can reduce enemy armor by several means, will that effect your chances?

- is it decided by: base weapon damage, +mods, +skills, +buffs, +whatever else

- etc...

 

[Hollowprime]

I'll just quote my past self. Damn that was harder to dig up than I thought.. It's in the context of another thread, but summed up the decap system somewhat decent:

Yeah that makes sense.

Still the perk description is very misleading. I personally like my games describing every bit of hidden mechanic because I like to use those to my advantage (e.g. the luck perk in new vegas would allow for weapons with multiple bullets to critical many times, but criticals would also benefit from higher critical damage).

A word from a developer would be nice..

 

[Hollowprime]

Another question, is the dismemberment chance algorithm the same for all zombie parts? If I use a knife to break the leg of a zombie is it flat percentage or is it based on the formula you described?

 

[Umbrella]

In the xml, we have

<passive_effect name="DismemberChance" operation="base_add" level="2,10" value=".05,.45"/>

So there is a variable which is additively affected by DismemberChance. Even if it has a base value (maybe 0.05), and even if it multiplies another weapon- or damage- based variable, the variation with a constant weapon should be around 5% / level

 

[theFlu]

Another question, is the dismemberment chance algorithm the same for all zombie parts? If I use a knife to break the leg of a zombie is it flat percentage or is it based on the formula you described?

As far as I could tell, yes, it's the same for heads and limbs. The main difference is, you'll do double to triple damage via headshots, so the zombie dies sooner, actually lowering the chance of "decapitation before death". In other words, per swing chance is the same, per enemy is less for heads..

 

[Hollowprime]

I'm going to run a test and see if having max dismembering chance (50%) makes knives cut the legs of zombies half the time on easy then max difficulty. And with different weapons too.

 

[Hollowprime]

On insane difficulty stabbing 20 times the leg of an enemy feral biker does not destroy his leg at all. 20% dismemberment chance.

 

[meganoth]

On insane difficulty stabbing 20 times the leg of an enemy feral biker does not destroy his leg at all. 20% dismemberment chance.

Well, do the math: If each stab does (for example) 1/20th damage of the total HPs of the biker (I assume the 20th stab did kill the biker), your dismemberment change would be exactly 20% for this one biker.

Do this treatment to 5 bikers and on average one of them should have his leg removed.

 

[Hollowprime]

Well, do the math: If each stab does (for example) 1/20th damage of the total HPs of the biker (I assume the 20th stab did kill the biker), your dismemberment change would be exactly 20% for this one biker.
Do this treatment to 5 bikers and on average one of them should have his leg removed.

Well your math is wrong. I could not dismember anything from the multiple bikers I tried normal and power attack stabbing with a level 5 hunting knife and 20% chance for dismemberment .

Funnily enough not even the club seems to work on those guys.A level 2 pummel pete has a 70% chance to knock down foes with power attacks yet not even those seem to work on zombies (particularly the bikers).

There is something awfully wrong about the perk descriptions. I think it's either the bikers that have full protection against stuns/dismemberment OR the stun chance is also working in a similar way to the dismemberment chance (or something else like difficulty settings).

The perks need some serious description changes or those are some bugs we're talking about. I bet on the first...

 

[theFlu]

Hmm, that sounded odd, so I loaded my test world.. insane, 10/10 Agi (50% dismemberment) and 5/5 Deep cuts (I'd guess half my damage was bleed damage since it takes ages to stab a biker...).

I'll confirm the dismemberment is nowhere near "50% of enemies" there. I didn't have the will to keep on stabbing beyond 10, after seeing one, at most two legit dismembers that far. (Hitting a corpse after death has a lot higher chance to chop it up, saw a couple of those, not sure about one of the two I had)

The descriptions are pretty inaccurate all around.. they're slowly improving, but there's plenty of ground to cover yet..

EDIT: Actually.. the bleed damage might be so high as to explain my results, but that would require too much maths for me to do right now.. sorry (If it's actually half my damage, the outcome should be 2,5 dismembers per 10 targets, and getting one would be nicely within variation..)

 

[meganoth]

Ok. Did a test myself now. Did not use the biker, because the biker has "Physical Damage Resist" 20 aka armor. Did use difficulty nomad so that everything is at 100%. Used the fat hawaian (without armor). Hit points 300. Got me a q6 machete with one mod, so it made exactly 30 HP damage aka 10% of his HP. Turned on hitpoints display on the zombies. Gave myself 10 agility and 5 flurry o blows (for weapons speed), no points in Deep cuts.

Then spawned in 25 hawaians, turned off their AI. Hit them on their leg 7 times or until the leg came off. With bleed their hp were down to about 40 after 7 hits because I had to make a pause between each hit. They always stumbled and I needed them to stand still for assured hits

Ok, I did 62 hits and got 3 legs off. Expectation would have been 1/10*50% = 5%.

5% of 62 is 3.1. In this case it checks out quite well.

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I bungled my first test, by the way. I crouched sometimes, counted some glancing hits, hit them until they were dead which resulted in sometimes more or less hits per zombie. Practically I didn't get dependable numbers from that. But with that in mind I got 12% per hit. It seems the damage bonus of 100% for stealthed hits is counted for the dismemberment chance !!

If you make tests you have to take into account all variables. If for example you test on insane difficulty and make only 1/4 of the damage or the zombies have 4 times the HPs (I don't remember which way it was), then you probably will also get 4 times less dismemberments.