A smite spell affects a single smite attack that a character makes. Smite spells are identified and defined by having a target entry of "smite attack". Any attack that counts as a smite attack for whatever reason can be targeted by such a spell. This does not grant the caster an extra attack, it simply modifies an attack that would otherwise be made. All of the smite spells presented here have target entries of "your smite attack", meaning that they only target smite attacks that the caster herself makes, but other variations are possible and may be used by spells in later supplements.
Note that while most smite spells only provide benefits to smite attacks directed against valid subjects of the smite ability being used (that is, subjects against which the smite applies its effects), not all do.
Author's Note: If you're reading this and are scared off by the wall of text, don't worry. How the smite spells presented here work is intuitive from their descriptions; you cast the spell while smiting, and the smite attack gets stronger or the smite target gets some negative effect on them. Most of this section deals with theoretical expansions of the concept that may be used in future supplements, and a little behind-the-scenes insight into how some of the spells' format was developed. The only thing important to note that may be at all unclear is that the smite spells that allow saves and SR do so against the target of the smite using the spell's parameters (caster level, save DC, etc.), not those of the smite attack (in the case of a form of smite that allows a save, for example), and that dispelling the spell does not in anyway undo the effects of the smite that carried it.
Components: Since personal smite spells must be cast alongside the caster making an attack, the caster rarely has a free hand. Consequently, none of the personal smite spells presented here have any somatic, material, or focus components, all of which would require a free hand.
Casting Time: A smite spell must be cast any time from immediately prior to the attack be declared up to the first moment that the attack is been declared to be a smite attack. Usually this means immediately prior to the attack being resolved, before the attack roll is made, certain special smite abilities may allow a character to declare a smite attack later in the process. Consequently, all such spells that affect the caster's own smites have casting times of 1 swift action or 1 immediate action, and those that affect the smites of other characters usually have casting times of 1 immediate action. Those with other casting times can only target smite attacks made as a readied action to coincide with the completion of the spell's casting, although smite spells with casting times of 1 standard action can also be timed the other way around (cast as a readied action to coincide with the smite attack).
Range: The creature making the smite attack must be within the indicated spell range. There is no limitation on the range at which the smite's target can be affected.
Target: A spell with a target entry of "smite attack" affects a single smite attack that a character makes. Any attack that counts as a smite attack for whatever reason can be targeted by such a spell. Smite spells usually qualify that. Personal smite spells have a target of "your smite attack", while those that affect other creatures' smite attacks might have target entries like "an ally's smite attack".
Author's Note: This format for targeting entries was adapted and expanded from the breath-modifying (meta breath) spells found in Draconomicon and Spell Compendium.
Duration: Smite spells usually have two effects. The first is an effect that modifies a single smite attack. This is always instantaneous. The second effect is the actual modification applied. This may have a duration, indicating how long the target of the smite is affected. The second effect is a product of the spell itself, not the smite attack, so dispelling it only removes the spell's effect, not that of the smite attack that carried it, nor of any other secondary effects caused by other smite spells applied to the same smite attack.
Because smite spells always have a duration of instantaneous for their first effect, their duration entry is usually not included in their spell descriptions in order to reduce clutter and improve readability, and only the duration of the second effect is included.
Saving Throw and Spell Resistance: As described above, smite spells usually have two effects. The first effect of a personal smite spell is always harmless and allows no saving throw or spell resistance. The first effect of a non-personal smite spell is most often harmless and allows spell resistance and a Will save to negate, although some are different. For spells where a save or spell resistance is offered as part of the first effect, the subject that makes the smite attack is the one whose spell resistance and saving throw may be applied.
The second effect, being the actual modification applied, may allow a saving throw or spell resistance independently of whatever method was used to deliver the smite itself. These entries indicate how the target of the smite can resist the effects of the smite spell. In any case, the second effect is a product of the spell itself, not the smite attack, so saving against it, resisting it with spell resistance, and so forth only affect the spell's effect, not that of the smite attack that carried it.
For example, consider a hypothetical spell that enhanced an ally's smite attack by allowing it to paralyze creatures hit by it for several rounds. The first effect would instantaneously modify the smite, and the second effect would cause paralysis for 1 round/level on a failed Fort save. It might have the following entries:
Casting Time: 1 immediate action
Range: Close (25 ft. + 5 ft./2 levels)
Target: An ally's smite attack
Duration: 1 round/level
Saving Throw: Will negates (harmless); Fortitude negates
Spell Resistance: Yes; Yes
Thus, on a successful smite attack, the subject of the smite would suffer the full normal effects of the smite attack, and would be paralyzed for a number of rounds equal to the spell's caster level on a failed Fort save (against the spell's save DC), assuming that the subject did not have sufficient spell resistance to resist the spell (using the spell's caster level). Should the ally who made the smite attack be unwilling, she could have applied her spell resistance (if any) and made a Will save against the spell's save DC in order to prevent it from applying entirely.
Because personal smite spells are always harmless and allow no saving throw or spell resistance for their first effect, their saving throw and spell resistance entries are usually not included in their spell descriptions in order to reduce clutter and improve readability, and only the save or spell resistance of the second effect is included.
26/6/2017: Updated formatting regarding capitalization and a couple minor other things.
22/6/2017: Reposted in Min Max Forum.
17/6/2016: Moved seeking smite from a 1st-level spell to 2nd-level and reverted its attack bonus to +20.
5/6/2016: Reduced seeking smite's attack bonus from +20 to +10.
28/2/2016: Removed acid from the damage types available to admixtured smite and energized smite. Like elemental smite and as described in the spell lists, they only do cold, electricity, or fire damage.
30/11/2015: Added the missing heal planar servant spell for celestial servant ACF paladins.
29/11/2015: Distant smite now only applies to melee smite attacks. Clarified greater piercing smite. Fixed typos in anchoring smite.
27/6/2014: Fixed typo in greater dispelling smite's short description.
18/6/2014: First posted.