[ThatGuyThatIAm]

Spells save versus certain, well, saves. An example:

----

Caustic Mist
Classes:
None
Description:
2: Decrease Hitpoints by 500 per tick

Details: Raw spell data
Spell Type: Detrimental
Skill: Innate
Mana: 0 Target
Type: PB AE
Casting Time:
Instant Duration: 1 ticks @L1 to 4 ticks @L8
Recast Time: 24
Resist: Disease (-300)
Fizzle Time: 0.00
Range to target: 0
AE Radius: 60
Interruptable: Yes
Location: Any
Time of Day: Any


Messages:
Other cast: Soandso spits a glowing mist.
Cast on you: Your skin begins to rot.
Cast on other: Soandso 's flesh begins to liquefy.
Effect Fades: Your skin regains its solidity.

----
For this spell you'd want high (VERY high) disease resists to save versus the spell (resist it). Same goes for magic, but in the spell data, it'd have Resist: Magic ( xxx ). High MR is helpful when fighting, for example, Aerin Dar with his nasty AoE.