Abilities

Weapon of Choice (Level 1): The weapon master forms a powerful bond with one type of weapon. Whenever wielding this weapon type, he will get many additional benefits, which improve as he gains experiences.
Ki Damage (Level 1): Once per day maximum damage can be dealt.
Increased Multiplier (Level 5): The weapon of choice gains an additional 1x to its critical damage multiplier. (i.e., 2x becomes 3x, etc.)
Superior Weapon Focus (Level 5):Superior Weapon Focus (Level 5)
Ki Critical (Level 7): Add +2 to weapon of choice threat range

Weapon Master - Epic Levels (level 21+)

The weapon master's bond with his weapon of choice becomes stronger and devastatingly effective as he becomes the epic weapon master.
Hit Die: d10
Skill Points: 2+ Int Modifier every level
Bonus Feats: 1 bonus feat every three levels
Superior Weapon Focus: For every five levels gained an additional +1 to attack is granted to the Weapon of Choice.

Epic Weapon Master Bonus Feats List

Armor Skin, Damage Reduction, Devastating Critical, Epic Toughness, Epic Prowess, Epic Weapon Focus, Improved Whirlwind Attack, Overwhelming Critical, Superior Initiative.