Weapon Training (Ex): A weapon master's levels are considered to be levels in fighter for purposes of qualifying for feats. For example, a character who is Fighter 5/Weapon master 5 can take Weapon Supremacy.

Ki Pool (Su): A weapon master can channel her ki to manifest special powers of weaponplay. She can use her ki powers a number of times per encounter equal to one-half her class level (minimum 1) plus her Wisdom bonus (if any). Her ki pool is refreshed after 10 minutes of rest. Ki powers can be used only if a weapon master is wearing no armor, use no shield, and is unencumbered. 

As long as a weapon master's ki pool isn’t empty (that is, as long as she has at least one use remaining), she gains a +2 bonus on her Will saves. She must be wearing no armor and must be unencumbered to benefit from this bonus.

A weapon master's ki powers are ki damage, ki critical, and ki whirlwind. Each power is described under a separate entry below.

AC Bonus (Ex): A weapon master is highly trained at dodging blows, and she has a sixth sense that lets her avoid even unanticipated attacks. When unarmored and unencumbered, a weapon master adds her Wisdom bonus (if any) to her Armor Class. This ability does not stack with the monk's or ninja's AC bonus ability (a weapon master with levels of monk or ninja does not add the bonus twice). In addition, a weapon master gains a +1 bonus to AC at 5th level. This bonus increases by 1 for every five weapon master levels thereafter (+2 at 10th, +3 at 15th, and +4 at 20th level).

These bonuses to AC apply even against touch attacks or when a weapon master is flat-footed. The character loses these bonuses when she is immobilized or helpless, when she wears any armor, when she carries a shield, or when she carries a medium or heavy load.

Bonus Feats: At every odd level, a weapon master gets a bonus combat-oriented feat. These bonus feats must be drawn from the feats noted as martial feats. A weapon master must still meet all prerequisites for a bonus feat, including ability score and base attack bonus minimums. 

These bonus feats are in addition to the feat that a character of any class gets from advancing levels. A weapon master is not limited to the list of martial bonus feats when choosing these feats.

Ki Damage (Su): Starting at 2nd level, once per round, after a weapon master score a hit with a weapon, she can spend one encounter use of ki pool to take the maximum damage with that weapon by. For example, if a weapon master uses a longsword, she would calculate the damage as if she rolled a 8 on her damage roll of 1d8.

This ability cannot be used when you roll a successful critical hit.

Starting at 6th level, a weapon master deals double maximum damage with the weapon if she uses Ki damage. All other damage modifiers are not affected by this ability.

Art of Parry (Ex): Starting at 3rd level, a weapon master gains +1 shield bonus to her AC when she is wielding a weapon. This bonus is doubled if she is fighting defensively or uses total defense. She loses this bonus if she wears any armor, carries a shield, or carries a medium or heavy load.

Every two levels beyond 3rd, Art of Parry grants one additional shield bonus.

Ki Critical (Su): Starting at 4th level, once per round, a weapon master can spend one encounter use of ki pool to extend her weapon's crit range by two for a single attack. This only additively stacks with Improved Critical, keen enchantment, and any other effect that increases a weapon's critical range. For example, a weapon master using a keen longsword and ki critical would threaten a critical on a roll of 15 through 20. (19-20 doubled is 17-20, then add two for 15-20)

Starting at 10th level, a weapon master adds four to her weapon's crit range when she uses Ki critical.

Ki Whirlwind (Su): Starting at 6th level, a weapon master can spend one encounter use of ki pool to make an attack against every foe within reach. This ability does not take an action, but she can only use this ability once per round.