When your character joins multiple guilds, they gain different skills from each of these guilds. Because you have skills from various guilds, a penalty on both the experience and gold required to level is applied to certain guilds.
WARNING: This section gets moderately mathematical, so if you
are not very good at mathematics, the following could be confusing.
All studies are based on real multiplay character data or hexedited
single character data. This document only addresses various statistics
associted with the game. It is not intended to give you direct guidence
on how to actually play the game. However, the statistics will help you
greatly decide your game play strategy! I am sure some of you hardcore
Demise fans will love to know about them. :)
I have divided this report into 2 sections:
1) How is guild experience related to race, guild, penalty, and level?
2) How is guild penalty related to guild and level?
Vamp has a couple of spreadsheet penalty calculators (In different
Excel formats  I think) available for download at his website http://www.geocities.com/Tokyo/Field/1288/
Section 1)
How is guild experience related to race, guild, penalty,
and level?
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This study confirmed the formula I last posted. The exp required to go from level L to level L+1 is:
ExpForNextLevel(L) = Constant * RaceFactor * GuildFactor * (1 + Penalty) * L
Total exp required for level L is:
TotalGuildExp(L) = Constant * RaceFactor * GuildFactor * (1 + Penalty) * (L * (L  1) /2 )
Constant is around 22.0.
RaceFactor is 1.000 for Human(3), 1.0582 for Yeti(4), 1.1055 for Dwarf(5),
1.1471 for Ogre/Troll(6), 1.1854 for Elf/Giant/Gnome(7), 1.2217 for Saris(8).
All four digits are correct values.
GuildFactor is the ExFt from the official Guild Statistics. It is 8
for Artisan, 16 for Warrior, 32 for Cleric etc.
Penalty is your guild penalty.
This formula is tested on pure character. The character only joins one guild and level that guild to level 100, 200, 300, and 400. This formula is very accurate, with a relative error of less than 1%.
Section 2)
How is guild penalty
related to guild and level?
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Penalty is the most difficult, and yet, most interesting part of my study. The result actually turns out to be pretty simple.
Many of you have guessed that penalty
is closely related to guild abilities. Your guess is correct. First of
all, let me put some official guild abilities statistics. Note that ''Guild
Abilities' for penalty is different from the guild abilities you see by
pressing F7.





















































































































Penalty(G) = PenaltyConstant * (TotalAbilities
 GuildAbilities(G, L))
Penalty Constant is a constant around
0.030. TotalAbilities is your total abilities from all guilds you join.
GuildAbilities is the abilities contributed only by your guild G at level
L.
The formula for GuildAbilities(G, L) is:
GuildAbilities(G, L) = GuildTotalAbilitiesFactor(G)
* L / 100
GuildTotalAbilitiesFactor(G) is
the last column in my guild ability table. It is 16 for Artisan, 32 for
Warrior, 30.5 for Explorer, 17 for Warlock, etc.
For instance, if you have a Warrior
at 100, then your guild abilities from warrior are:
GuildAbilities(Warrior, 100) = 32
* 100 / 100 = 32.
The formula for TotalAbilities is a little complex. It is the sum of all your 7 abilities.
TotalAbilities = MaxThieving + MaxBackstabing + MaxCriticalHit + ... + MaxLanguage
MaxThieving is the maximum thieving ability from all your guilds. Note that your thieving ability is not added from various guilds, but the max of them. Suppose you are guild G1 at level L1, guild G2 at level L2, ..., guild G_n at level L_n.
MaxThieving = Max(ThievingGuild_1, ThievingGuild_2, ..., Thieving Guild_n).
ThievingGuild_1 is the thieving ability
contributed by your guild G1 at level L1. It has a linear relationship
with respect to guild level L1.
ThievingGuild_1 = Guild1ThievingFactor
* L1 / 100.
Guild1ThievingFactor is the thieving
factor for your guild G1. It is from the guild ability statistics table.
Thieving is 5 for artisan, 2 for warrior, 3.5 for explorer, 9 for thief,
etc.
To sum up the formula for TotalAbilities,
Suppose you are guild G1 at level L1, guild G2 at level L2, ..., guild
G_n at level L_n.
TotalAbilities = SUM (MAX (GuildAbilityFactor(i, j) * Li / 100) )
GuildAbilityFactor(i, j) is the ability
factor for guild Gi for ability j. Li is the level of guild Gi. The SUM()
is for j (for all 7 abilities). The MAX() is for i (for all guilds).
Some examples. If you only has one
guild, then your total abilities is exactly the same as the abilities contributed
from your only guild. So
TotalAbilities = GuildAbilities
The penalty for your only guild
is 0:
Penalty = PenaltyConstant * (TotalAbilities
 GuildAbilities) = 0
This comes at no surprise.
If you have a Warrior 100, and Artisan
1. Then almost all your abilities come from your Warrior. Your warrior
will get 0.0 penalty. Penalty for your Artisan 1 is:
Penalty(Artisan) = PenaltyConstant
* (TotalAbilites(Warrior, Artisan)  GuildAbilities(Artisan))
= 0.03 * (WarriorAbilities(100))
= 0.03 * (32 * 100 / 100)
= 0.96
So Warrior 100 gives your Artisan 1 a penalty of 1.0! It equals to the actual number form character data!
Things get interesting when you have multiple guilds. Suppose you have a Warrior 100 and a Thief 100.
WarriorAbilities = 32 * 100 / 100
= 32
ThiefAbilities = 32 * 100 / 100
= 32
The following table is for guild abilities and to calculate total abilities.




































So TotalAbilities = 52
Penalty(Warrior) = 0.03 * (TotalAbilities  WarriorAbilities) = 0.03 * (52  32) = 0.60 (Actual penalty is 0.5)
Penalty(Thief) = 0.03 * (TotalAbilities  ThiefAbilities) = 0.03 * (52  32) = 0.60 (Actual penalty is 0.5)
Penalty(Other Guild) = 0.03 * (TotalAbilities  OtherGuildAbilities) = 0.03 * (52  0) = 1.56 (Actual penalty is 1.6. Suppose the other guild is low level around 1.)
If you are a Warrior 100, Wizard
200, then:




































TotalAbilities = 50
Penalty(Warrior) = 0.03 * (TotalAbilities  WarriorAbilities) = 0.03 * (50  32) = 0.54 (Actual penalty is 0.5)
Penalty(Wizard) = 0.03 * (TotalAbilities  WarlockAbilities) = 0.03 * (50  34) = 0.48 (Actual penalty is 0.4)
Penalty(Other Guild) = 0.03 * (TotalAbilities  OtherGuildAbilities) = 0.03 * (50  0) = 1.50 (Actual penalty is 1.5. Suppose the other guild is low level around 1.)
One final example, for Artisan/ Warrior/ Explorere/ Thief/ Wizard/ Cleric.
All level 100.





















For most samples I calcuated, the errors range between 5% to 15%. The error is caused by the 12 digit accuracy in the official guild abilities table. They probably used a table that is slightly different to calculate penalty.
Recall the penalty formula can be written as
G= 0.0003*(GiLi  GF*L)
Here are the Guild Factor's ranked in order
Guild Factor(GF)
Ninja 40
Warri 32
Thief 32
Villa 31
Explo 30.5
Palad 26
Barba 25.5
Magi 17
Warlo 17
Sorce 16
Artis 16
Cleri 15
The higher the GF, the easier it is for you to level out of a penalty, as your GF*L factor increases. So the ninja is easiest to level out of a penalty, and cleric is worst. So, try and level up in those guild which have a low GF first, otherwise they will suffer a heavy penalty  increasing as the GF gets lower.