In an upcoming Pathfinder campaign, one of my friends that loves to attempt to break games is about to take the Summoner class. Out of caution and curiosity, I looked through the advanced evolutions that his character could purchase and got stuck on Limbs as shown around the middle of this page. The major problem with the rules written as they are is that they give a static BAB for the creature without additional attacks (aside form natural attacks), set a rule where each pair of arms needs an evolution for either a natural attack or an overall weapon profeciency in order to use them in battle, but completely neglect to mention how extra arms wielding weapons work.
In the end, I would like to know this:
Does having extra limbs give the Eidolon additional weapon attacks, or does it just give it weapon options in a battle without the risk of invoking attacks of opprotunity?