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School transmutation; Level druid 2, ranger 2
Casting Time 1 standard action
Components V, S, DF
Target living creature touched
Duration 10 min./level
Saving Throw none; Spell Resistance yes (harmless)
Barkskin toughens a creature's skin. The effect grants a +2 enhancement bonus to the creature's existing natural armor bonus. This enhancement bonus increases by 1 for every three caster levels above 3rd, to a maximum of +5 at 12th level.
The enhancement bonus provided by barkskin 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.