Overly Loyal (3.5e Flaw)
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 Incredible Loyalty [General]
You are incredibly loyal to your allies.
Prerequisite: Must be in a group of some sort, cannot adventure solo
Effect: You are unable to leave combat if you have any allies in it. During combat, if an enemy hits an ally for more than 1/4 of their maximum health, you must succeed a will save (DC 10+1/2 of the amount by which the damage exceeded 1/4 of the ally's max hp) or attack them on your turn (other actions may be made normally, but you must use some form of attack against that enemy and all attacks must be made against them, unless they are already dead). If more than one enemy dealt the necessary amount of damage, you must attack the one that dealt the most damage, or one that downed an ally.
Benefit: 1 Bonus feat OR gain an extra +2 to hit when flanking.
Normal: You can attack whoever you want in combat.