Interaction With a Gestalt (3.5e Variant Rule)
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 Interaction With a Gestalt
A psychic gestalt is considered a single mind for the purposes of psychic and mind-affecting abilities, although the individual personalities and identities (and free will) of the participants remain. Any time a member of the gestalt must make a Will save, it is made for the entire group, using the highest Will save bonus of the component minds, with a +2 bonus per additional mind in the gestalt. So a psychic gestalt with four minds adds a +6 bonus (for three extra minds) to the highest Will save bonus of the group when making Will saves.
A mind-affecting ability that affects one member of the gestalt affects them all equally. So psychic gestalts tend to be more resistant to psychic abilities, but are affected as a unit.