Aura versus Alignment
|Spell level :||Innate level: 8, Cleric: 8|
|Components :||Verbal and Somatic|
|Duration :||6 sec. * cLevel|
1 Round (cLevel)
|Spell resistance :||Yes|
When this spell is cast, you choose to be protected from either good or evil. You receive a +4 deflection bonus to Armor Class, immunity to mind-affecting spells and spell-like abilities used by creatures of the chosen alignment, and spell resistance 25 against spells cast by creatures of the chosen alignment. In addition, if Holy Aura is chosen, then the caster's attacks do a 1d6 divine energy damage bonus against evil-aligned creatures, and if Unholy Aura is chosen, then the caster's attacks do a 1d6 negative energy damage bonus against good-aligned creatures.
The description doesn't include anything about the +4 increase to all saves this spell provides against the chosen alignment. See doAura() in x0_i0_spells.nss - line 1401 (which is fired from both scripts).
This is not, as it implies, an Aura. It only affects the caster.
At the level it is gained (level 15), the spell resistance is about right to deflect spells (on the basis of 11 + Level of spell resistance, such as from the Monk ability). As levels progress, the bonus becomes less and less powerful however.
The armor class is a nice bonus, apart from at level 15 you are likely to have some magical items providing a similar bonus. The immunity to mind-affecting spells and +4 for all saving throws is very powerful against spellcasters.
The melee damage bonus is divine damage, meaning it usually cannot be resisted by any means.
If you know you'll be battling Good or Evil, while the duration is only worthwhile for a single battle, this provides many bonuses against the chosen alignment, both defensive and offensive.
This gave a damage shield instead of a damage bonus. The change was made to a damage bonus due to the damage shield working against anything, rather then just the chosen alignment. For technical reasons the damage shield could not be forced against a specific alignment.