How the chance of extracting a working bionic from a zombie is calculated?

Game Talk The Bunker
1

I’ve started a new character in 0.C, and I would really like to get some bionics to start with (they’re mostly uncraftable, the only ones I can craft are aero-evaporator, cranial flashlight and power-storage). I don’t want to raid labs as I don’t have good computer skill and labs are a real pain, in general (idk why I literally freeze every-time I enter one).

Zombies are an easy source, shockers’ lightening doesn’t deal much damage and they tend to fire lightening between intervals, giving me enough time to kill them. Shocker-Brutes are a problem but they’re still easier than killing a hulk.

But there is one problem, I don’t know what factors play in getting a working cbm from a zombie. I think somebody on this forum said that butchering quality of weapon doesn’t matter, and survival skill matters. My survival skill is 6 right now so I’m avoiding most of the bionic-zombies, the ones I’ve killed, I’ve left them un-butchered. But now its becoming really annoying; I cleared a large horde, killed every single one of them; I came back a little while later only to find the area filled with shockers/shocker-brutes which I didn’t (B)utcher/(s)mash, got almost fried to death (looks like electricity ignores armor). But as I butchered one shocker, I got two burnt out bionics, the other yielded the same; so I left the shocker-brute un-butchered, again (as they drop good bionics).

My question is How can I increase the chances of getting a working bionic? I want to get good bionics without going inside the labs. I know that high-level bionics are inside the labs but mid-level and beginner bionics should be obtainable from the zombies, I guess. I remember butchering a zombie scientist with a circular-saw(on) in 0.B, and not getting any useful results, so I’m pretty sure butchering-quality doesn’t matter.

2

Butchering quality does matter because the get bionics roll is a combination of dexterity, survival skill and the tools butchering quality but once you are good enough that you always get all of the bionics increasing your survival skill or butchering quality wont get you better bionics or less burnt out bionics.

3

First random float from 0 to survival skill level - 3 adds to skill_shift
Then random float from 0 to 0.25 * (DEX - 8) adds to skill_shift
Then if you have less than 4 STR you get pentaly to skill_shift equal 0.25 * (5 * (4 - STR))
If you have inconsistent weapon, you also get penalty equal 0.2 of incosistenty.

If you got not negative “skill_shift” there is a 50% chance you will get burnt out bionic, otherwise it will be working one.

So no, the chance of getting burnt out or working CBM is constant.

4

So thats the reason I got burnt out bionics even while using circular saw; the 0.B character had 10 survival iirc.

[quote=“EditorRUS, post:3, topic:10081”]First random float from 0 to survival skill level - 3 adds to skill_shift
Then random float from 0 to 0.25 * (DEX - 8) adds to skill_shift
Then if you have less than 4 STR you get pentaly to skill_shift equal 0.25 * (5 * (4 - STR))
If you have inconsistent weapon, you also get penalty equal 0.2 of incosistenty.

If you got not negative “skill_shift” there is a 50% chance you will get burnt out bionic, otherwise it will be working one.

So no, the chance of getting burnt out or working CBM is constant.[/quote]

So… How to increase the chances of getting a working bionic if my Survival-Skill is 6 and DEX is 12. I think a butcher knife should work as circular saw requires something called sawblade, and I don’t have it.

5

[quote=“EditorRUS, post:3, topic:10081”]First random float from 0 to survival skill level - 3 adds to skill_shift
Then random float from 0 to 0.25 * (DEX - 8) adds to skill_shift
Then if you have less than 4 STR you get pentaly to skill_shift equal 0.25 * (5 * (4 - STR))
If you have inconsistent weapon, you also get penalty equal 0.2 of incosistenty.

If you got not negative “skill_shift” there is a 50% chance you will get burnt out bionic, otherwise it will be working one.

So no, the chance of getting burnt out or working CBM is constant.[/quote]

That seems awfully easy - if you have 8 or more dex and 3 or more survival, basically, you just flip a coin for each bionic slot the corpse has (2 for shocker, 2 for scientist, 3 for shocker brute, etc)?

What is this “inconsistent” thing?

6

Not quite related, but with the recent experimentals it seems somewhat easy to nab a power storage bionic from NPCs. Heck, my current pretty late game character is finding power storages in all the NPCs that were unfortunate enough to be around my character.

7

That is odd, didn’t know NPCs could spawn with CBMs.

Indeed, that part is a bit unclear.

Also, what happens when ‘skill_shift’ is negative? I assumed you then always get a broken cbm.

Updated this: http://www.wiki.cataclysmdda.com/index.php?title=Survival

8

Perhaps EditorRUS means weapons with bad butchering quality.

9

Wrong word, sorry.

Perhaps EditorRUS means weapons with bad butchering quality.
Exactly.
So... How to increase the chances of getting a working bionic if my Survival-Skill is 6 and DEX is 12. I think a butcher knife should work as circular saw requires something called sawblade, and I don't have it.
Didn't I say? You can't change it. It's a solid 50% chance. The only thing you change is the chance of getting CBM when you butcher a corpse.
That seems awfully easy - if you have 8 or more dex and 3 or more survival, basically, you just flip a coin for each bionic slot the corpse has (2 for shocker, 2 for scientist, 3 for shocker brute, etc)?
Survival skill matters far more.
10

[quote=“EditorRUS, post:9, topic:10081”]Wrong word, sorry.

Perhaps EditorRUS means weapons with bad butchering quality.
Exactly.
So... How to increase the chances of getting a working bionic if my Survival-Skill is 6 and DEX is 12. I think a butcher knife should work as circular saw requires something called sawblade, and I don't have it.
Didn't I say? You can't change it. It's a solid 50% chance. The only thing you change is the chance of getting CBM when you butcher a corpse.
That seems awfully easy - if you have 8 or more dex and 3 or more survival, basically, you just flip a coin for each bionic slot the corpse has (2 for shocker, 2 for scientist, 3 for shocker brute, etc)?
Survival skill matters far more.[/quote]

From what you wrote, nothing matters “more” if everything is positive. That is, once survival hits 3, dex is at least 8, str is at least 4, and you don’t have a weapon with a negative butchering quality, BAM, there’s no chance of failure. More survival no longer helps at that point.

11
From what you wrote, nothing matters "more" if everything is positive. That is, once survival hits 3, dex is at least 8, str is at least 4, and you don't have a weapon with a negative butchering quality, BAM, there's no chance of failure. More survival no longer helps at that point.
One problem:
First random float from 0 to survival skill level - 3 adds to skill_shift Then random float from 0 to 0.25 * (DEX - 8) adds to skill_shift
random float from 0 random float from 0
According to normal distribution theorem it still possible to fail at butchering with high skills and DEX but the chance is lower.
12

[quote=“EditorRUS, post:11, topic:10081”]

From what you wrote, nothing matters “more” if everything is positive. That is, once survival hits 3, dex is at least 8, str is at least 4, and you don’t have a weapon with a negative butchering quality, BAM, there’s no chance of failure. More survival no longer helps at that point.

One problem:

First random float from 0 to survival skill level - 3 adds to skill_shift Then random float from 0 to 0.25 * (DEX - 8) adds to skill_shift
random float from 0 random float from 0
According to normal distribution theorem it still possible to fail at butchering with high skills and DEX but the chance is lower.[/quote]

If that is true, then what you wrote earlier is not true. Those two things are not compatible.

If I have 3 or more survival, the first test will never be negative.
If I have 8 or more dex, the second test will never be negative.
If I have 4 or more str, the third test will never be negative.
If I have a weapon that is not “inconsistent” (I’m assuming you mean it has a negative butchering quality?), then the fourth test will never be negative.

If you add 4 numbers that are not negative, you will NEVER get a negative number. Ever. The end. All portions of the normal distribution will be non-negative.

13

Yep, you get a guaranteed drop at higher levels.

This wasn’t rebalanced for a looooong time. I changed it twice - once to roll per-part rather than once so that you can get a drop of 1 CBM and not always 0 or 2, then second time to use floats rather than ints. Neither of those was really a rebalance.

If someone has good suggestions (“rescale the survival part to be 0 to 10 rather than 0 to 3, but double its weight in roll” could be good, “make it more random” is not), preferably with examples on how would it get better, we could fix it up.

14
If I have 3 or more survival, the first test will never be negative. If I have 8 or more dex, the second test will never be negative. If I have 4 or more str, the third test will never be negative. If I have a weapon that is not "inconsistent" (I'm assuming you mean it has a negative butchering quality?), then the fourth test will never be negative.
Ah, I get it. You are right.
15

[quote=“Coolthulhu, post:13, topic:10081”]Yep, you get a guaranteed drop at higher levels.

This wasn’t rebalanced for a looooong time. I changed it twice - once to roll per-part rather than once so that you can get a drop of 1 CBM and not always 0 or 2, then second time to use floats rather than ints. Neither of those was really a rebalance.

If someone has good suggestions (“rescale the survival part to be 0 to 10 rather than 0 to 3, but double its weight in roll” could be good, “make it more random” is not), preferably with examples on how would it get better, we could fix it up.[/quote]

Personally, I think the vast majority of CBMs should have to be either crafted from scavenged CBM parts (disassemble multiple scavenged Dielectric Capacitance, for instance, before you get all the bits to make a functional one) or found ready to go (dropped very rarely or found in stores/bunkers/etc).

When butchering a corpse, random roll for what bionics they have, then a semi-random roll for damage (a pulped corpse should have more damaged bionics), then a skill/stat check of some kind to scavenge the bionic.

The skills involved are probably correct, but yes, making it scale better and continue to have some level of fail chance (doing more damage to the scavenged parts, for instance) until higher level would be better. Perhaps “survival skill - CBM difficulty”? That would make some things work reliably at low levels (Power Storage, Internal Chronometer) but not others (Night Vision, Teleportation, etc).

Also, the mechanism makes it very much pass/fail, with little sense of improvement. If you start the game with 8 str/8 dex, and you have a decent butchering tool, you going to fail ALL THE TIME until you hit Survival 3, then you’re going to pass ALL THE TIME. That’s not good.

Instead of a flat “if it’s negative, you get nothing, if it’s positive, you have a 50/50 to get something”, make it more like “50 + result *25 percent chance to get something” - if you do well, you’ll more likely get it, if you do poorly, you’ll make likely get nothing, but it won’t be a simple pass/fail.

One more thought:

The description of how CBMs work makes great sense and is very convenient for use in the game… but absolutely ridiculous when it comes to scavenging an installed bionic from a corpse. All the bits that do the installing would not be in the body to get back.

If you don’t want to work out exactly how to make every kind of CBM, make a recipe (or similiar mechanism) that simple takes so many scavenged CBMs (with damaged ones counting only partial, maybe?) to get a whole one ready to install.

The “burnt out bionic” mechanism seems like stub for a system like this - as is, it’s kinda silly (and you tend to end up with LOTS of burnt out bionics - those should take several to make a working one, as they are “burnt out”, right?).

16

I had an idea to make CBMs cause pain, and inject you with a painkiller. (this way you cannot binge install).

As the CBM is an automated install kit. (being able to get a whole install from a corpse is a bit odd imho).

Of course then you would also need healing items to make CBMs, have CBMs that come out of corpses be incomplete kits (without the automated install system). And my system became a bit of a nuisance quickly after that. (in the thought experiment).