Diablo Item Rarity Calculator

[the Langolier]

Diablo Item Rarity Calculator

This is a javascript utility that can be used to calculate the rarity of any magical item in terms of any single game's chance to create the item. It also displays the best dungeon level to find the item and the best drop probabilities from various sources. The program also allows rarity calculations for multiple base items and affixes. It does not calculate rarity from items available for purchase at the vendors.

The calculations were based on several assumptions:

• Values from Jarulf's Guide, chapter 3.8 (item creation in dungeons) were used
  <>
  
• Average dungeon layout modeled by the information from the chapter dealing with unique item rarity.
  <>
  
• All spells have an equal chance of being chosen (probably not accurate). Any information about spell selection will be appreciated
  <>
  
• Valid for Diablo v1.09 multiplayer only<>
  [st]
  Sample Output:
  Awesome Full Plate Mail of the Suffix:
  *******************************************
  
  Rarity:
  0.4157539% 1 in 240 games
  0.4236866% (N) 1 in 236 games
  0.4236866% (H) 1 in 236 games
  
  Best drop probability:
  0.1759345% dlvl 15 (n,N,H)
  1) 0.3850823% Armor Rack (dlvl 15)
  2) 0.0263684% Sir Gorash(Blood Knight,n,N,H) Arch-Bishop Lazarus(Advocate,n,N,H)
  3) 0.0006973% Soul Burner(mlvl 30,n,N,H) Blood Knight(mlvl 30,n,N,H) Advocate(mlvl 30,n,N,H)
  
  Rarity:
  Given as both a probability of any one game creating the item and as the statistical number of games that would need to be cleared to find the item for all three difficulties. The rarity will normally be the same for all difficulties except for those items that has a base item qlvl higher than that of both affixes.
  
  Best drop probabilty:
  The three top probabilities will be chosen from: 1 unique enemy (or multiple if 2+ unique enemies have the same drop probabiltiy), 1 normal enemy, and 1 dungeon source. Because of this, there may be larger probabilities than those that are displayed 2nd or 3rd, but I thought it would be boring if the list contained nothing but unique enemies. Also, including various sources helps users determine the best areas to find the item.
  
  Please feel free to give suggestions (just remember they are just that) or report errors/bugs. I would ike to include armor/weapon rack probabilites into the final rarity calculation as well, so any information about their generation rates would be helpful (I was estimating 1 armor and 1 weapon rack per game). Also, if anyone else is willing to host the calculator it would be much appreciated, website maintenance is not my forte.
  
  Thanks to those who participated in the Monster Creation thread for insight on a very important aspect of the rarity calculations (all the normal monsters!). Special thanks to Jarulf for the help and, of course, for the information about item creation in his guide. This calculator would not have been possible without either of these.

[the Langolier]

Think that obsidian/zodiac is rare? HA! It appears it is far from.

With a new calculator, I thought it might be fun to play around with it. Do you think you know what the rarest item in the game is? Reply with your top (or bottom...) guesses. The largest value out of the three difficulties will be the one used as your entry*.

Any screenshots showing your favorite item with its rarity will be welcome too. Have fun!

*This unofficial "contest" is just for fun, and is in no way sponsored by the Moderating team

[LennyLen]

Email me if you'ld like some assistance with expanding your applet to function with Hellfire and D/HF mods. I've written several C applications which perform similar calculations on data they extract straight from the .exe itself. These could quite simply be modified to extract all the data you need from any mod and store it in some appropriate Java data structures that the applet can switch between at runtine to give the correct output for each .exe version.

[EDIT]Oops, I forgot to add... these are the structs I use in C, of this is of any help.[/EDIT]

[Sr.Juez]

Why in the prefixes' menu one can choose two values for crimson?:

Crimson (+21-30%)
Crimson (+31-40%)

BTW, if it is bug free, GREAT tool. Now we will know the best places to look for shields of blocking, gold jewlery, items of corruption, jewlery of Balance...

May I enter the rarity contest with?:

King's Great Sword of Haste:
*******************************************

Rarity: 0.0150573% 1 in 6641 games
0.0150533% (N) 1 in 6643 games
0.0150533% (H) 1 in 6643 games

Best drop probability:
0.0063747% dlvl 15 (n,N,H)
1) 0.0013370% Weapon Rack (dlvl 14,15)
2) 0.0010141% Sir Gorash(Blood Knight,n,N,H) Arch-Bishop Lazarus(Advocate,n,N,H)
3) 0.0000232% Soul Burner(mlvl 30,n,N,H) Blood Knight(mlvl 30,n,N,H) Advocate(mlvl 30,n,N,H)

EDIT:

I checked JG and found the answer for myself. Curious. So many years playing Diablo and I still hadn't noticed that there are two values for Crimson. Sorry about the stupid question, and thanks for the Diablo Item Rarity Calculator.

[Mick]

Well, the first thing I looked up was my favourite bow of all time, found long ago with my first multiplayer character:

Emerald Long War Bow of the Heavens:
*******************************************

Rarity: 0.0061654% 1 in 16219 games
0.0061654% (N) 1 in 16219 games
0.0061654% (H) 1 in 16219 games

Best drop probability:
0.0044045% dlvl 15 (n,N,H)
1) 0.0013571% Sir Gorash(Blood Knight,n,N,H) Arch-Bishop Lazarus(Advocate,n,N,H)

I never knew how lucky I was to find that one!

Great program, Lang.

Mick.

[LemmingofGlory]

Why in the prefixes' menu one can choose two values for crimson?:

Crimson (+21-30%)
Crimson (+31-40%)

Because Blizz used the name for two different prefixes. Same name, but different effect (21-30 res vs 31-40 res), price, and qlvl.

[o: *LEMMING* :o]

[LennyLen]

Because Blizz used the name for two different prefixes. Same name, but different effect (21-30 res vs 31-40 res), price, and qlvl.

I remember from playing around with the Beta EXE that there will still two seperate names for the two 'Crimsons.' I believe that the second one was Burgundy. How they managed to overwrite that with a second Crimson by the time of the commercial release is anyone's guess. ;)

[Bolty]

Dragon's Amulet of the Zodiac:
*******************************************

Rarity: 0.0562098% 1 in 1779 games
0.0562098% (N) 1 in 1779 games
0.0562098% (H) 1 in 1779 games


Did I play in 1,779 games? Maybe :) My most prized possession of Diablo 1. Never did find an Obs/Zod, though.

Awesome app, Langolier!

-Bolty

[DeeBye]

Code:

Awesome Full Plate Mail of the Stars:
*******************************************

Rarity: 0.0390341%     1 in 2561 games
       0.0397580% (N) 1 in 2515 games
       0.0397580% (H) 1 in 2515 games

Best drop probability:
  0.0168713%  dlvl 15 (n,N,H)
1) 0.0350074%  Armor Rack (dlvl 15)
2) 0.0026368%  Sir Gorash(Blood Knight,n,N,H) Arch-Bishop Lazarus(Advocate,n,N,H)
3) 0.0000633%  Soul Burner(mlvl 30,n,N,H) Blood Knight(mlvl 30,n,N,H) Advocate(mlvl 30,n,N,H)

Neat. A dlvl 15 Armor Rack is exactly where I found mine. Nice utility. *bookmarks*

[Scorzonera]

Seems like Emerald Bastys are pretty scarce, too.

Emerald Bastard Sword of Haste:
*******************************************

Rarity: 0.0024436% 1 in 40922 games
0.0024436% (N) 1 in 40922 games
0.0024436% (H) 1 in 40922 games

Best drop probability:
0.0017735% dlvl 15 (n,N,H)
1) 0.0005070% Sir Gorash(Blood Knight,n,N,H)

[Walkiry]

Not to talk about BN equipment:

Vulnerable Full Plate Mail of the Pit:
*******************************************

Rarity: 0%
0% (N)
0.0018229% (H) 1 in 54856 games

Best drop probability:
0.0006311% dlvl 4 (H)
1) 0.0000084% Devil Kin(mlvl 5,H) Corpse Bow(mlvl 5,H) Hidden(mlvl 5,H)
2) 0.0000063% Dark One(mlvl 7,H) Burning Dead Archer(mlvl 7,H) Blink(mlvl 7,H)


But the one I always wanted is not so rare after all:

Topaz Tower Shield of Blocking:
*******************************************

Rarity: 0%
0.0210946% (N) 1 in 4740 games
0.0208472% (H) 1 in 4796 games

Best drop probability:
0.0052589% dlvl 6 (N)
1) 0.0035585% Goretongue(Rotting Carcass,N) El Chupacabras(Plague Eater,N)
2) 0.0000475% Horror Captain(mlvl 8,N) Bone Gasher(mlvl 8,N) Flesh Clan(mlvl 8,N) Flesh Clan Archer(mlvl 8,N)

[Scorzonera]

And Emerald bows of Lightning. :lol:

Emerald Bow of Lightning:
*******************************************

Rarity: 0%
0% (N)
0% (H)

Best drop probability:
0% dlvl 1 (n,N,Hdlvl 2 (n,N,Hdlvl 3 (n,N,Hdlvl 4 (n,N,Hdlvl 5 (n,N,Hdlvl 6 (n,N,Hdlvl 7 (n,N,Hdlvl 8 (n,N,Hdlvl 9 (n,N,Hdlvl 10 (n,N,Hdlvl 11 (n,N,Hdlvl 12 (n,N,Hdlvl 13 (n,N,Hdlvl 14 (n,N,Hdlvl 15 (n,N,Hdlvl 16 (n,N,H)
1) 0% Large Chest (dlvl 1,1,1,1,2,2,2,2,3,3,3,3,4,4,4,4,5,5,5,5,6,6,6,6,7,7,7,7,8,8,8,8,9,9,9,9,10,10,10,10,11,11,11,11,12,12,12,12,13,13,13,13,14,14,14,14,15,15,15,15,16,16,16,16)

[the Langolier]

Emerald Long War Bow of Lightning:
*******************************************

Rarity: 0.0061654% 1 in 16219 games
0.0061654% (N) 1 in 16219 games
0.0061654% (H) 1 in 16219 games

All better.

Thanks for catching that error. Due to the way I found the selected suffix in the array of affixes (it goes through the suffix list and then the spell list) it would replace "Lightning" suffix, qlvl 21, with the "Lightning" spell, qlvl 3. It didn't affect the number of valid suffixes that could drop, so all that was afffected was items of Lightning.

[Walkiry]

Vulnerable Buckler of Corruption:
*******************************************

Rarity: 0.0049244% 1 in 20306 games
0.0025677% (N) 1 in 38944 games
0.0024945% (H) 1 in 40087 games

Best drop probability:
0.0016392% dlvl 3 (n)
1) 0.0000297% Large Chest (dlvl 3)
2) 0.0000220% Devil Kin(mlvl 5,n) Corpse Bow(mlvl 5,n) Hidden(mlvl 5,n)
3) 0.0000137% Black Death(mlvl 6,n) Horror(mlvl 6,n) Burning Dead Captain(mlvl 6,n) Shadow Beast(mlvl 6,n)



Wow, lucky me ^_^

EDIT: By the way, as many of you would have correctly guessed, that shield actually gives me +2 AC when I wear it.

[Pu uhonua]

Using Walkiry's idea of looking at cursed items...

Vulnerable Full Plate Mail of Brittleness:
*******************************************

Rarity: 0%
0% (N)
0.0003284% (H) 1 in 304417 games

Best drop probability:
0.0001817% dlvl 2 (H)
1) 0.0000069% Carver(mlvl 3,H) Skeleton Archer(mlvl 3,H) Fiend(mlvl 3,H)


And another thing... I get the following error for a Fine Full Plate Mail of the Dark
Line: 2836
Char: 9
Error: 'validSuffix[...].cursed' is null or not an object

Great app! And it's alot of fun to play with too.

[the Langolier]

And another thing...&nbsp; I get the following error for a Fine Full Plate Mail of the Dark
Line: 2836
Char: 9
Error: 'validSuffix[...].cursed' is null or not an object

Fine Full Plate Mail of the Dark:
*******************************************

Rarity: 0%
0.0062226% (N) 1 in 16070 games
0.0147923% (H) 1 in 6760 games

In the function to calculate drop prob. from an armor rack, I forgot to remove the array element [i] when I copied the part that found all valid suffixes and changed it to the part that determined if the selected suffix could drop. At that point, it wouldn't be checking an array, therefore it didn't know what [i] was supposed to mean. Good eye.

A dually cursed affix full plate mail is what I too found to be the most rare. Specifically, one whose affixes JUST make the qlvl/2 - qlvl range which only allows one monster level to drop it. Rusted Full Plate Mail of the Fool gives the same results.

[Daemon]

I don't know what kind of axe was that famous BNM's Useless axe of tht Pit but that sure was a (un)lucky find! ;)


Useless Broad Axe of the Pit:
*******************************************

Rarity: 0.0019303% 1 in 51804 games
0.0024625% (N) 1 in 40608 games
0.0024159% (H) 1 in 41391 games

Best drop probability:
0.0007323% dlvl 4 (N)
1) 0.0000116% Large Chest (dlvl 4)
2) 0.0000056% Devil Kin(mlvl 5,N) Corpse Bow(mlvl 5,N) Hidden(mlvl 5,N)
3) 0.0000054% Devil Kin(mlvl 5,H) Corpse Bow

[Sr.Juez]

Prefixed Shield of Deflection:
*******************************************

Rarity: 9.8930304% 1 in 10 games
9.9882700% (N) 1 in 10 games
9.9882700% (H) 1 in 10 games

Best drop probability:
3.3599255% dlvl 15 (n,N,H)
1) 0.3691578% Stareye the Witch(Hell Spawn,n,N,H) Bloodlust(Hell Spawn,n,N,H) Blackjade(Hell Spawn,n,N,H) Red Vex(Hellspawn,n,N,H) Steelskull the Hunter(Steel Lord,n,N,H) Sir Gorash(Blood Knight,n,N,H) The vizier(Cabalist,n,N,H) Arch-Bishop Lazarus(Advocate,n,N,H)
2) 0.0223430% Decapitated Body (dlvl 15)
3) 0.0088917% Soul Burner(mlvl 30,n,N,H) Blood Knight(mlvl 30,n,N,H) Advocate(mlvl 30,n,N,H)

Eeerm... Langolier, the maximum prefix of that kind in a shield is absorption (-3).

I wouldn't trust a programmer whose programs "don't have bugs".

[fatherbrainLBL]

Tee hee... Have I found it? I just might have...(I don't have one tho...)
Useless Bastard Sword of the Fool:
*******************************************

Rarity: 0%
0.0011008% (N) 1 in 90839 games
0.0010591% (H) 1 in 94410 games

Best drop probability:
0.0003796% dlvl 4 (N)
1) 0.0000056% Devil Kin(mlvl 5,N) Corpse Bow(mlvl 5,N) Hidden(mlvl 5,N)
2) 0.0000054% Devil Kin(mlvl 5,H) Corpse Bow(mlvl 5,H) Hidden(mlvl 5,H)

[fatherbrainLBL]

Then again...
Sharp Great Sword of Fragility:
*******************************************

Rarity: 0%
0.0003729% (N) 1 in 268117 games
0.0003337% (H) 1 in 299661 games

Best drop probability:
0.0002063% dlvl 2 (N)
1) 0.0000079% Carver(mlvl 3,N) Skeleton Archer(mlvl 3,N) Fiend(mlvl 3,N)
2) 0.0000071% Carver(mlvl 3,H) Skeleton Archer(mlvl 3,H) Fiend(mlvl 3,H)