Appearing below the school of magic in the spell description, when applicable, is a descriptor that further categorizes the spell in some way. Some spells have more than one descriptor.
Some of these descriptors have no game effect by themselves, but they govern how the spell interacts with other spells, with special abilities, with unusual creatures, with alignment, and so on. eg. A mind-affecting spell works only against creatures with an Intelligence score of 1 or higher. A creature immune to fear is immune to all spells with the fear descriptor.
Descriptor(s) also indicate type of saving throws for spells that allow them. For example, a shield dwarf character receves +2 bonus for saving throws against spells with "Poison" descriptor. Note that saving throws may only have one type, even if the spell uses multiple descriptors. Most common example of this are fear-causing spells - as fear is a mind effect by itself, any fear spell/ability is blocked by immunity to mind-affecting effect. At the same time, "fear" and "mind-affecting" are different types of saving throws, fear spells/abilities use the former saving throw type. In other words, "immunity to mind-affecting" effects works against fear effects too, but "bonus to saving throws against mind-affecting effects" doesn't.
It is also helpful for roleplaying in the NWN2 game engine, as in DnD 3.5 no good-aligned cleric would ever cast a spell with an evil or negative spell descriptor, and while the game engine does not enforce this it makes it easier for those wanting to abide by such rules.
Unfortunately, there are a lot of bugs with descriptor system - sometimes description mention wrong, obsolete or even non-existant descriptors. Sometimes - doesn't mention them at all. Both situations at the same time are also possible.
Functioning NWN2 descriptors[]
- Acid
- Cold
- Electricity
- Fire
- Sonic
- Divine
- Negative
- Death
- Poison
- Disease
- Mind-affecting
- Fear
- Weapon enchantment
- Armor enchantment
- Healing
- Paralyze*
- Darkness**
*Paralyze is the special case; like "Fear", it is a special mind-affecting effect that is blocked by general "immunity to mind-affecting" yet its saving throws are not of that type. Unlike "Fear", paralyze effects do not have their own internal type and saving throws against them are neutral. It is possible that at some point they were planned to through. In any case, in the final game only Stonehold mentions this descriptor but all "Hold" spells/abilities work this way, so "Paralyze" kinda exist like an invisible pseudo-type.
** Darkness doesn't do anything in practice. It was supposed to interact with mechanics that allow to see in it but it is bugged and doesn't work.
False descriptors[]
- Evil
- Magical armor
- Gas
- Force
- Figment
- Compulsion
- Nature
- Water
- Teleportation
- Chaos
- Pattern
- Air
- Earth
Those are just words in the descriptions and nothing else. They do not actually affect game mechanics and are either blindly copied from PnP descriptions or were considered during development but ultimately abandoned (like Evil).
See also: Subschools
DnD 3.5 comparison[]
- 3.5 ruleset also includes: chaotic, good, language-dependent, lawful and light in the base role alone, with additional books adding more.
- 3.5 ruleset does not include: divine, negative, poison, disease, weapon/armor enchantment, paralyze, gas, figment, compulsion or healing.
- Many of the NWN2 descriptors are subschools in DnD 3.5 and function in a similar way.