Source: Dragon #315
Your rage gives you fearsome speed and agility.
Prerequisite: Ka-tainted, ability to rage, Dex 13
Benefit: When you rage, you may choose to use your normal rage benefits or gain the benefits provided by this feat instead. If you choose to gain the benefits provided by this feat, you can gain a +4 bonus to Dexterity, a +4 bonus to Constitution, and your base land speed increases by 10 feet. However you take a -2 penalty to Will saves. Also, you can continue to use Dexterity-based skills while using this feat, but you still cannot use Charisma or Intelligence-based skills with the exception of Intimidate. These effects replace all normal effects of a rage.
A Rage of the Raptor lasts for a number of rounds equal to 3+ the character's Constitution modifier. A character can prematurely end his rage. At the end of the rage, barbarian loses the rage modifiers and restrictions and becomes fatigued (-2 penalty to Strength, -2 penalty to Dexterity, can't charge or run) for the duration of the current encounter, unless the character has another ability that prevents these side effects of a rage, such as the 17th-level barbarian's tireless rage ability.
Special: Characters with the greater rage class ability gain a +8 bonus to Dexterity and Constitution, and a total base land speed increase of 20 feet. Character with the mighty rage class ability gain a +8 bonus to Dexterity and Constitution and a total base land speed increase of 30 feet. In either of these cases, the Will save penalty remains -2.
Normal: A character engaging in a rage gains a +4 bonus to strength, +4 bonus to Constitution, and a +2 morale bonus on Will saves, but he takes a -2 penalty to Armor Class.