Spiderskin

Underdark (Und)Forgotten Realms (3.5)
School
Transmutation
Casting Time
1 standard action
Components
V, S, M, DF
Range
Touch
Target
One creature
Duration
10 minutes/level
Saving Throw
Will negates (harmless)
Spell Resistance
Yes (harmless)

Spiderskin makes the subject’s skin tougher and more like a carapace.
The spell grants the recipient a +1 enhancement bonus to its existing natural armor bonus, a +1 racial bonus on saves against poison, and a +1 racial bonus on Hide checks.
Each of these bonuses increases by 1 for every three caster levels above 3rd, for a maximum of +5 at caster level 12th.
The enhancement bonus provided by spiderskin stacks with the target’s natural armor bonus, but not with other enhancement bonuses to natural armor.
A creature without natural armor has an effective natural armor bonus of +0, much as a character wearing only normal clothing has an armor bonus of +0.
Material Component: A piece of a spider.