Bane of the Unclean
(Lords of Madness, page 44, DnD 3.5)
[General]
A creature with this feat hates aberrant beholders so strongly that it gains bonuses when fighting them.
Prerequisite
True beholder or must have aberration as a favored enemy
Benefit
The creature gains a +2 morale bonus on attack rolls, weapon damage rolls, touch Armor Class, and saving throws when fighting a beholderkin.
Special
If the creature is a true beholder, the benefi ts of this feat apply to other true beholders as well as to beholderkin.