Gruesome Vengeance (4e Feat)
From D&D Wiki
Gruesome Vengeance [Racial]
+2 to damage against cat's vengeance target.
Prerequisite: Rakshasa, cat's vengeance racial power
Benefit: You get a +2 feat bonus to the damage roll of the attack against your cat's vengeance target. The bonus increases to +4 at 11th level and to +6 at 21st level.