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 D20
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This article is a D20 reference page
The System Reference Document is a comprehensive toolbox consisting of rules, races, classes, feats, skills, various systems, spells, magic items, and monsters compatible with the d20 System version of Dungeons & Dragons and various other roleplaying games from Wizards of the Coast.
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Amulet of Natural Armor: This amulet, usually crafted from bone or beast scales, toughens the wearer’s body and flesh, giving him an enhancement bonus to his natural armor bonus of from +1 to +5, depending on the kind of amulet.
Faint transmutation; CL 5th; Craft Wondrous Item, barkskin, creator’s caster level must be at least three times the amulet’s bonus; Price 2,000 gp (+1), 8,000 gp (+2), 18,000 gp (+3), 32,000 gp (+4), or 50,000 gp (+5).
System Reference Document -> Magic Items: Wondrous Items