Introduction

I thought the old tables (31 and 32) in the DMG didn't do enough justice to the variability found in monsters. I wanted to make a table that added a bit more detail so that monster experience could be calculated more accurately. The result is the list provided below.

Table 1 - Experience Points according to Hit Dice and Modifiers from Table 2

How to use this Table

To determine the number of experience points to award for overcoming enemies, find the Hit Dice of the creature. Creatures with X+4 Hit Dice to X+9 Hit Dice count as the next higher category on the Creature Experience Point Value Table, and creatures with X+10 Hit Dice and up are considered two categories higher. This number is the base Hit Dice number for the creature. To this base number possible modifiers are added. These modifiers are listed on the Hit Dice Value Modifiers Table. After adding these modifiers, the total Hit Dice is calculated, and referenced on the Creature Experience Point Value Table to get the total experience point value. Half modifiers are counted by adding the half of the amount for rising to the next xp level to the total, (i.e. a creature which gives a total of 12˝ Hit Dice is worth an experience total of 3,000 plus 500 for 3,500 XP).

Table 2 - Hit Dice Value Modifiers

Guidelines to using the New Experience Point Value Table

1. No ability can be counted twice in any case
(Spell use of 1st through 6th Level spells gives a modifier of +2, not +3.)

2. If more than one modifier is applicable the greater one is counted.
(Gorgon breath would be a +2˝ modifier as Petrification, instead of a +2 modifier as Major Breath Weapon.)

3. When dealing with a power not listed on this table, use the most similar power to determine it´s modifier
(Constriction from a Couatl would be about the same as the Hug of a Owlbear, so it would be a +1 modifier, Terror is the same as Fear etc.)

4. Abilities must have the possibility of usage to be counted.
(An Aaracockra for example would get no modifier for his flying capability if in low-roofed dungeon. If the same Aaracockra would be encountered walking in the open plains, the modifier would count, even if the Aaracockra is killed before taking to the air.)

5. Hit Die Modifiers from abilities falling under a general title can be normally be counted only once.
(A Vampire is vulnerable to holy water, running water, sunlight and wooden stakes etc., but all these modifiers are stand under the same title, Vulnerability to Uncommon Attack Forms, so the total modifier is only -˝. In extreme case, the DM might decide to count an ability under a general title twice. For example, Black Puddings are immune/resistant to cold, lightning, blows and mind affecting spells, these altogether justify a +2 modifier instead of the normal +1)

6. If a creature has some really powerful abilities, or lots of them, its reasonable to double or even triple some modifiers.
(A 30th lvl mage would get at least +6 for his spell ability instead of +3 for a 18th lvl mage.)

7. This table is meant to better calculate XP values, it is in no way complete or perfect as a compromise between simplicity and realism must be found.

Clarifications

A. Physical Combat Related Abilities
In these table may be included all magical and non-magical, non-spell modifications to these abilities. Girdles of Giant Strength increase the Maximum Damage per round, Rings of Protection the Armor Class. See also under F. Magical Items.

B. Special Combat Abilities
Under this letter the more tricky abilities are mentioned, which are hard to classify. Would disguise be an Special Attack or Defense From, etc. Common sense must dictate when to count these abilities. Enhanced Surprise encompasses thing like concealment, stealth and camouflage. Disguise encompasses things as physical disguises, voice mimicry etc. An Example ; A Kech who hides himself in the foliage and uses it´s mimicry voice ability to lure and attack pc´s by surprise it would get +1 Hit Die Modifier from Intelligent Tactics/Cunning OR a +1 Hit Die Modifier from Enhanced Surprise ˝ + Disguise ˝, but not +2 for all abilities, because this is in contradiction with rule 1.

C. Spell Ability
Spells which duplicate certain abilities are not counted as those abilities, as this is in contradiction with rule 1. A Haste spell for example, would not give a greater Hit Die Modifier by increasing the number of attacks per round.  

D. Special Attack Forms
This letter receives modifiers of +˝ to +3, the rationale behind the height of this modifier is that abilities which cause relatively permanent incapacitation (i.e. Death, Petrification) with no save, or a negative one, will receive +3, The same abilities with a normal save would get +2˝. Lesser incapacitating abilities, which are temporary or more easily overcome (i.e. Fear, Paralyzation), receive a +2 modifier. And abilities which cause somewhat increased damage, and are dependent upon attack rolls or saves, receive a +1 modifier.

Clarification on categorizing some abilities :
Draining, Minor - Temporary, easy to correct
Draining, Major - Permanent, difficult to correct
Poison, Minor - Causing weakness, minor damage, revulsion
Poison, Major - Causing death, major damage, incapacitation
Cause Disease/Affliction, Minor - Slow, mild, easy to cure
Cause Disease/Affliction, Major - Fast, fatal, difficult to cure
Sound Attack, Major - Permanent effect, causing death, difficult to resist
Sound Attack, Minor - Temporary effect, easy to recover from

E. Special Defense Forms
This letter also receives modifiers from +˝ to +3

Clarification on categorizing some abilities :
Reduced Damage from Certain Weapons - Half damage from slashing/piercing weapons, etc.
No Damage from Certain Weapons - Immune to bludgeoning, nonmagical, hit only by silver, cold iron,, etc.
No Damage from Weapons below +X - This includes significantly reduced damage from +(X-1) and lower weapons.
Immunity/Resistance to Common attack Form - Fire, Lightning, Cold, Mind Affecting Spells
Immunity/Resistance to Uncommon Attack Form - Ghoul Paralyzation, Some Spells, Acid

F. Magical Items
Magical items which duplicate certain abilities are counted as those abilities, if they are mentioned in one of the above tables. A Ring of Regeneration would count as Regeneration, a Ring of Fire Resistance would count as an Immunity or Resistance to a common attack Form; i.e. Fire. Magical items must duplicate abilities on a relatively permanent basis. Use of Bracers of the Blinding Strike would not be modified if the user would get more attacks per round. Magical items which can´t be classified can be counted under Using Magical Items, however this can be done only once, as in rule 1, even if the wearer has ten items which would affect combat.

G. Penalties to Experience
These give a negative modifier to the final Hit Dice total. They must only be calculated if there´s a significant disadvantage, for example, Orc´s have a -1 penalty in sunlight, this is to minor to be counted as a special vulnerability. Rakshasas who can be killed by blessed crossbow bolts however is enough.

Clarification on categorizing some abilities :
Vulnerability to Common Attack Forms - Fire, Lightning, Slashing/Piercing Weapons
Vulnerability to Uncommon Attack Forms - Holy Water, Wooden Stakes, Light