Spellbook distribution research thread.

[Blank4u47]

It was pointed out by soirana that we should post a thread instead of derailing his. I quite agree.

So here goes.

The goal here is to create a character and compare the results after accumulating 100 spellbooks and counting them. This only counts for monster drops, not guaranteed sources such as the sage etc.

The purpose of this is to see what percentage of spellbooks are frost bolt/lightning for necro/druid respectively.

Anyone who can lend a helping hand in this endeavor will be helping to possibly improve the game's spellbook distribution.

[JellySlayer]

Relevant RFEs 3798 (http://www.adom.de/forums/project.php?issueid=3798) and 3696 (http://www.adom.de/forums/project.php?issueid=3696)

[Soirana]

Relevant RFEs 3798 (http://www.adom.de/forums/project.php?issueid=3798) and 3696 (http://www.adom.de/forums/project.php?issueid=3696)
Well, reports are prone to deliver extremes of possible RNG... since people are more likely report abnormalities

More on topic my first 25 books (troll necro r60 wand born I2-5) starting books not included


Calm monster
Cure serious wounds
2xDarkness
Farsight
5xFrost Bolt
2xInvisibility
Know alignment
2xLight
Magic Missile
2xRemove Curse
Scare monster
2xSlow monster
Slow poison
Strength of atlas
Teleportation
Web

p.s. also dropped Confucius book

Gonna keep SoA and drop rest.

I think the book problem actually varies in between versions, but I rarely play casters.

[Cactus]

I'd be very happy to generate some data.

Thanks for the links, JellySlayer. I wasn't aware of the more recent one. It appears TB already tried to reproduce the problem:


I just used debug mode to test this further with a dwarves druid (currently on D: 16). I generated lots of random spell books and received the following distribution (which looks totally ok to me)

So how exactly were these spellbooks generated? What is the difference between debug mode and a normal game? Maybe that's where to look for the problem?

In the meantime, generating more resilient data from actual games surely cannot hurt.

[Soirana]

So how exactly were these spellbooks generated? What is the difference between debug mode and a normal game? Maybe that's where to look for the problem?

Normally debug mode is not something retail version is shipped with.

Go ask Thomas if you need details.

[Soirana]

Got another 25


Acid Bolt
Calm monster
Cure light wounds
darkness
Fire bolt
7-Frost bolt
Ice ball
Improved fireball
Knock
Light
Magic Missile
neutralize poison
2xSlow monster
Slow poison
SoA
Summon monsters
2xWeb


Overall 12/50, So my crude estimate (lol) would be 24%...

[yhal003]

RNG in adom is very strange sometimes. 100 books as a sample size should be plenty if there is a simple percentage, but there is no way you get 66 books or more with 0.25 chance - the probabilities are minuscule. Try playing with this for example http://www.vassarstats.net/textbook/ch5apx.html.

I don't have much experience with spellbook drops playing non-spellcasters most of the time. But some other item types often drop in a very bizzare fashion. For example my last game had no eternium boot drops and only single non-brass bracers pair. It is like there is a seed rolled on start that determines drop probability for the rest of the game.

I don't think this question can be resolved without some code diving or preloading custom random functions.

[Blank4u47]

RNG in adom is very strange sometimes. 100 books as a sample size should be plenty if there is a simple percentage, but there is no way you get 66 books or more with 0.25 chance - the probabilities are minuscule. Try playing with this for example http://www.vassarstats.net/textbook/ch5apx.html.

I don't have much experience with spellbook drops playing non-spellcasters most of the time. But some other item types often drop in a very bizzare fashion. For example my last game had no eternium boot drops and only single non-brass bracers pair. It is like there is a seed rolled on start that determines drop probability for the rest of the game.

I don't think this question can be resolved without some code diving or preloading custom random functions.

Yep, rng can be wierd sometimes, which is why I'm asking for the distributions from several people. 100 as a sample size is too low even for real life statistics.

[yhal003]

100 as a sample size is too low even for real life statistics.

Depends on percentage but you are probably right in this case. With 25% and 100 books, 3 deviations is between 12 and 38 drops which is quite a wide range (still 66 is way outside that).

[Soirana]

Depends on percentage but you are probably right in this case. With 25% and 100 books, 3 deviations is between 12 and 38 drops which is quite a wide range (still 66 is way outside that).
I hate to repeat, but is where actual list of 100 dropped books in which 66 are same?

Because all I've read were samples of <20, citations of spell knowledge and reported impressions (2/3 look differently when you read each book upon finding and actually calculate). Plus the only reports with numbers were r57.

Cause I grinned few mist elf necros in small cave and that seriously is not that bad.

p.s. slight decourse into Maths
66/100 and 12/50 is 0.52 if combined
with triple deviation on 100 set it would be -- 52+/-15
with triple deviation on 50 set it would be -- 26+/-11
So theoretically both observations still can be generated if chance is somewhere around 0.5. (They would be extreme lucky vs extreme unlucky, at 0.51 100 is in range of 36-66, while 50 is in 14-36 (with some stretches to rounding)).

p.p.s Sorear thought spells have rather straight drop chances. Well, again it just observation but in the last versions I don't really believe Light+Dark being ~20% in r60ish
http://www.it-is-law.com/adom/index.php?title=Spells

[Cactus]

I started a Salamander Wizard and sent him to the puppy cave. Fighting on PC:5 and dumping all spellbooks on the PC:4 staircase. Will post results once 100 spellbooks have been found.

[_Ln_]

Can't you guys start in exploration mode and repeatedly wish for "spellbooks". I would assume these wishes follow the same generation rules.

[yhal003]

Does not seem this way. Two books of frost bolt out of 60 or so, before my necromancer was crushed by his luggage.

[Soirana]

Can't you guys start in exploration mode and repeatedly wish for "spellbooks". I would assume these wishes follow the same generation rules.
I think this is more along the lines of what TB did with dev mode.

I thought about the topic (mostly making speculations out of experience, Sorear stuff and thin air --- mostly thin air ).

Well, it is very hard to believe german CEO would not know version control, so likely actual code for spellbook drops has not changed... but knowing Adom that code is very likely to dependent on some other parts...

So my thin air theory is that spellbook drop rate is somehow dependent on how difficult it is too read for char.... You know that explains why Dark/Light are common, wish rare and clericals have lower drop of balls/magical missile/etc.

There definitely fixes in starting books/spells/etc. So if starting books actually started generate bonus they were always supossed to give, that would explain why they magically started dropping frequently.

There was somesort of back fix after r57 (something with necros starting with elementalist spells or vice versa), which could have put frequency at something more reasonable...

End of the wild theory... Pleas, keep counting the spellbooks (if someone would do few hundred in r57 that would be great too)

[Blank4u47]

I figured it would be easiest to generate spellbooks using your living forest method with a necromancer and quickling corpses. Too bad no quicklings yet.

Edit: Soirana, your theory makes a lot of sense to me, I was getting about the same impression.

[SinsI]

Spellbook generation can be DL-dependent, so different people might get drastically different distributions due to different play styles.

How about using Create Item spell? It creates exactly the same item distribution you would get normally (though one need to check whether specific monster items - like slavemaster whips - screw it up compared to random generation), and it is easy to hack/automate it to continuously create loot.

[Blank4u47]

Spellbook generation can be DL-dependent, so different people might get drastically different distributions due to different play styles.

How about using Create Item spell? It creates exactly the same item distribution you would get normally (though one need to check whether specific monster items - like slavemaster whips - screw it up compared to random generation), and it is easy to hack/automate it to continuously create loot.

I can test the create item spell out with my troll, I have the spell now, along with the book, I just need great bookcaster and shadow touch now. However, I suspect it would work like the wish spell did.

[SinsI]

I don't suggest doing it on a non-cheater character - cheaters can freeze power points and memorization, thus having a much easier time casting the spells the enormous amount necessary to create a precise distribution (don't forget that Create Item creates all kinds of items, and not only spellbooks).

[JellySlayer]

Spellbook generation can be DL-dependent, so different people might get drastically different distributions due to different play styles.

I thought that spellbooks were all DL 1?

[Blank4u47]

I don't suggest doing it on a non-cheater character - cheaters can freeze power points and memorization, thus having a much easier time casting the spells the enormous amount necessary to create a precise distribution (don't forget that Create Item creates all kinds of items, and not only spellbooks).

I don't have the first clue how to create a cheater character, honestly. But it should go pretty quick with a necro lvl 25 in the gremlin cave.

[SinsI]

I don't have the first clue how to create a cheater character, honestly. But it should go pretty quick with a necro lvl 25 in the gremlin cave.

I used Artmoney and did a few trials: 500 casts in wilderness gave from 3 to 11 spellbooks on a human Fighter, and increasing LE to 69 from 10 didn't show any increase in the number, so that's one theory that is more or less disproved (LE-dependence).

[Soirana]

I thought that spellbooks were all DL 1?

Well, all weapon prefixes appear on DL1, but they are more common on weapons (presumably in uniform fashion) on higher Dl.

In other words these two ideas do not strictly contradict.

[Carter]

I thought that spellbooks were all DL 1?

iirc create item and wish are the only books which are not DL1.

[Soirana]

iirc create item and wish are the only books which are not DL1.

I've got create item in the mindcrafter archmage attempt, so this is not true...

[Soirana]

Another 25


Bless
3xCalm monster
Cure light w
Cure serious w
2xDarkness
Disarm
6xFrost bolt
2xIce ball
2XKnock
3cMagicMissile
Slow poison
2xStun ray

Overall: 18/75 Frost Bolt

[Soirana]

And last 25


Acid bolt
Bless
Darkness
Disarm trap
Fire bolt
Fireball
7xFrost bolt
Knock
5xLight
Lightning ball
2xLightning bolt
Magic Lock
Magic Missile
Teleportation


Overall -- 25/100

Hmmm... I thought it will be higher

[Carter]

25% is still a significant skew thats for sure, when you consider the 40 spells available.

[Cactus]

I'm done with the R60 Salamander Wizard that generated 100 spellbooks on PC:5. This took longer than I expected: 36000 turns were played, >5000 monsters killed and the char advanced to level 20. Testing with a Druid might be really tedious due to lower spellbook drop rate.

Here is the complete book drop list in order of appearance (starting books not included):


Fire Bolt
Light
Magic Lock
Fire Bolt
Knock
Web
Fire Bolt
Web
Fire Bolt
Revelation
Darkness
Strength of Atlas
Slow Monster
Lightning Ball
Slow Poison
Frost Bolt
Knock
Fire Bolt
Lightning Bolt
Invisibility
Darkness
Fire Bolt
Fire Bolt
Darkness
Light
Fire Bolt
Know Alignment
Invisibility
Fire Ball
Farsight
Stun Ray
Fire Bolt
Frost Bolt
Fire Bolt
Fire Bolt
Calm Monster
tract of chaos
Fire Bolt
Acid Ball
Slow Poison
Fire Bolt
Knock
Magic Missile
Burning Hands
Fire Bolt
Darkness
Darkness
Stun Ray
Fire Bolt
Fire Bolt
Slow Monster
Light
Fire Bolt
Know Alignment
Magic Lock
Fire Bolt
Death Ray
Light
Fire Bolt
Disarm Trap
Fire Bolt
Burning Hands
Invisibility
Darkness
Fire Bolt
Cure Light Wounds
Darkness
Fire Bolt
Acid Bolt
Slow Monster
Cure Light Wounds
Strength of Atlas
Strength of Atlas
Fire Bolt
Fire Bolt
Slow Poison
Darkness
Fire Bolt
Frost Bolt
Fire Bolt
Darkness
Stun Ray
Fire Bolt
delicate tome {destroyed by lightning lizard}
Frost Bolt
Light
Fire Bolt
Scare Monster
Fire Bolt
Knock
Fire Bolt
Slow Monster
Slow Monster
Burning Hands
Fire Bolt
Lightning Bolt
Knock
Frost Bolt
Fire Bolt
Magic Lock

And the .vlg:
http://pastebin.com/fryWZH6f

That's 32/100 books of Fire Bolt.

[SinsI]

I always thought this is a feature, not a bug - characters that specialize in a certain spell get more of its spellbooks, it is a bonus, not a replacement.

[Blank4u47]

I always thought this is a feature, not a bug - characters that specialize in a certain spell get more of its spellbooks, it is a bonus, not a replacement.

Me too, however, it seems a tad excessive at its current percentage. So the purpose of this thread is to get feedback from several people in hopes of getting a definite percentage before we report this as a better defined bug/rfe.

[Soirana]

I always thought this is a feature, not a bug - characters that specialize in a certain spell get more of its spellbooks, it is a bonus, not a replacement.
Well, that could explain, why TB had normal distro in debugmode... Maybe we could aks for proper explanation at this point or something.