Each unwilling creatures and magic items that emit sound in the silence spell's area of effect may make a Will save or use Spell Resistance to negate the effect of the spell upon them.
Area 20-ft.-radius emanation centered on a creature, object, or point in space
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Saving Throw: Will negates; see text or none (object); Spell Resistance: yes; see text or no (object)
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An unwilling creature can attempt a Will save to negate the spell and can use spell resistance, if any. Items in a creature's possession or magic items that emit sound receive the benefits of saves and spell resistance, but unattended objects and points in space do not.
Area: Some spells affect an area. Sometimes a spell description specifies a specially defined area, but usually an area falls into one of the categories defined below.
Regardless of the shape of the area, you select the point where the spell originates, but otherwise you don't control which creatures or objects the spell affects.
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Usually a harmful spell allows a target to make a saving throw to avoid some or all of the effect. The saving throw entry in a spell description defines which type of saving throw the spell allows and describes how saving throws against the spell work.Negates: The spell has no effect on a subject that makes a successful saving throw.