Magic Sensitivity (3.5e Feat)
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Magic Sensitivity [General]
Whenever a spell is cast nearby, the hair of your arms and neck rises, and you can feel the magical energy around.
Benefit: You can feel spellcasting within a 60-ft. radius of you. You can merely detect the presence or absence of spellcasting, never the location, strength, or number of spells being cast. This feat lets you become aware of normal spellcasting or through spell-completion items (such as scrolls), but it does not give you the ability to detect ongoing spells or magic items.