SRD:Martial Weapon Proficiency
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Martial Weapon Proficiency [General]
Choose a type of martial weapon. You understand how to use that type of martial weapon in combat.
You make attack rolls with the selected weapon normally.
When using a weapon with which you are not proficient, you take a –4 penalty on attack rolls.
You can gain Martial Weapon Proficiency multiple times. Each time you take the feat, it applies to a new type of weapon.
A cleric who chooses the War domain automatically gains the Martial Weapon Proficiency feat related to his deity’s favored weapon as a bonus feat, if the weapon is a martial one. He need not select it.