Two Weapon Fighting/table

Feat	Requirements	Offhand Strike Chance (Cumulative)	Other Benefits
Two Weapon Fighting	15 Dexterity	40%	Attack penalty reduced to -4/-4 from -6/-10 (Attack penalty reduced to -2/-2 if offhand is a Light Weapon) Increases the Hit Point bonus of Heroic Durability.
Improved Two Weapon Fighting	6 BAB, 17 Dexterity	60%	Increases the Hit Point bonus of Heroic Durability.
Greater Two Weapon Fighting	11 BAB, 17 Dexterity	80%	Increases the Hit Point bonus of Heroic Durability.
Perfect Two Weapon Fighting	Level 22, Epic Destiny Feat, Two Weapon Fighting	N/A	Your offhand attacks now doublestrike at 65% of the rate of your main hand, versus the base 50%, up to a maximum of 65%. Increases the Hit Point bonus of Heroic Durability.
Oversized Two Weapon Fighting	12 Strength, Two Weapon Fighting	N/A	Attack penalty reduced to -2/-2
Two Weapon Defense	Two Weapon Fighting	N/A	+2 DR when actively blocking and dual-wielding. +1 AC, +5 PRR, and +10 MRR cap when dual-wielding.