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Your eidolon is highly observant, and its link with you increases your own watchfulness.
Prerequisite: Eidolon class feature.
Benefit: While your eidolon is within your reach, you gain a +4 bonus on Perception checks. If you have 10 or more ranks in Perception, this bonus increases to +8. This does not apply if your eidolon is helpless or unconscious.