Racial Spell Cost Modifier

Every race has a racial spell cost modifer associated with it. There are three kinds of spells, arcane (mage/wzd/sor type), divine (cleric type) and psionic.

A negative modifier means the spell cost is lower.

Effective Mana

Note that the following shows the spell cost modifier. We can define the effective mana as the mana a human would need to cast the same amount as a particular race. If x is the racial spellcost modifier (in percentage), then the effective mana is 100 / (100 + x).

For example, a -25% spell cost modifier for sprite translates into 33% more effective mana.

Effective mana is the more directly useful notion, since finally, that's what determines how much you can cast.

Worship

The effect of worship on spellcost is multiplicative:

racial-modifier * (1 + worship-modifier) = cost-modifier

Bhyss (-10%) Sprite (75% normal cost):

0.75 * (1 + -0.1) = 0.675, which is 67.5% of regular cost - a 32.5% reduction.

Werredan (+10%) Minotaur (125%):

1.25 * (1 + 0.1) = 1.375, a 37.5% increase in cost, driving for example Foci from 400 to 550.

The values

The entries have been computed usually by checking spell cost for Foci for arcane (400 mana for hum atheist), Fortitudes for psionic (400) and Awen for divine (500) and then accounting for worship reduction using the Worship table.

Legend
Divine
Legendary
Great
Good
Average
Below Average
Bad
Absurd

Creatable Races Spell Cost Modifiers

Race	Arcane Modifier	Divine Modifier	Psionic Modifier
Centaur	-10%	-15%	-10%
Deep Gnome	-7%	-5%	-5%
Draconian	0	0	-5%
Drow	-12%	-10%	-10%
Duergar	+10%	-2%	+2%
Dwarf	+10%	-5%	+6%
Elf	-12%	-10%	-10%
Ent	0	-20%	0
Firedrake 1	-2%	-2%	-2%
Gargoyle	-15%	-5%	-5%
Giant	+10%	+10%	+10%
Gnome	-7%	-5%	-5%
Goblin	+10%	+10%	+10%
Halfling	0	0	0
Half-Elf	-6%	-5%	-5%
Half-Orc	+5%	0	+5%
Harpy	0	+15%	0
Human	0	0	0
Imp2	-10%	0	-10%
Kobold	30%	30%	30%
Kzinti	0	0	0
Lizardmen	0	0	-5%
Ogres	+10%	0	+10%
Orc	+10%	0	+10%
Troglodyte	+25%	+25%	+22.5%

Remort Races Spell Cost Modifiers

Race	Arcane Modifier	Divine Modifier	Psionic Modifier
Demonseed	-13%	-10%	-10%
Dragon	-10%	-10%	-15%
Drider	-2%	-5% (-14.5%)4	0%
Gith	-5%	-5%	-17%
Golem	0	+10%	+10%
Griffon	0	0	0
High Elf	-15%	-15%	-20%
Hobgoblin	+10%	+10%	+5%
Ignatur	-8% 3	0	-4%
Illithid	-10%	-20%	-35%
Minotaur	+25%	+15%	+25%
Miraar	0	0	-10%
Sprite	-25%	-25%	-25%
Troll	+10%	+15%	+15%
Tuataur	-10%	-10%	-20%

1 Firedrakes start with 0% spell cost reduction and gain -2% reduction after they evolve at hero 250
2 Spell cost reduction for a Pain Elemental, spell cost reductions is worse at other stages of evolution
3 -15% spell cost on fire spells for Ignatur
4 Drider base divine spell cost reduction is -5% however a drider only piece of chest armor exists (Shawl Of The Spider Goddess) which effectively reduces divine spells at lord to -14.5%.