With the aid of an ally, you are skilled at piercing the protections of other creatures with your spells.
Whenever you are adjacent to an ally who also has this feat, you receive a +2 competence bonus on level checks made to overcome spell resistance. If your ally has the same spell prepared (or known with a slot available if they are spontaneous spellcasters), this bonus increases to +4 and you receive a +1 bonus to the caster level for all level-dependent variables, such as duration, range, and effect.
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SECTION 15