Hate (3.5e Feat)
From D&D Wiki
Your hate for a specific creature allows you to be more proficient at killing them.
Prerequisite: Int 13
Benefit: The feat grants you the Favoured Enemy ability as if you were a 1st level Ranger.
Normal: You must take a level of Ranger to gain the Favoured Enemy ability.
Special: This feat may be selected multiple times. It's effects do not stack. Each time you select it you may choose a new favoured enemy.