Telepathic Eavesdropping (3.5e Variant Rule)
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A character with Psychic Sense and Mind Reading who senses a use of the Mental Contact skill can attempt to “listen in” on the mental conversation, intercepting the psychic transmissions. This requires a successful Psychic Sense check to detect the skill use, followed by a successful Mind Reading check (DC 15) to eavesdrop on the mental conversation. This eavesdropping isn’t detectable unless one of the participants in the mental contact also has Psychic Sense and detects the eavesdropper’s Mind Reading skill use. This means that many telepaths observe “mental radio silence” when they know that other telepaths are around and may be listening.