Eye for Eye

Eye for Eye is a perk in the Fallout: New Vegas add-on Honest Hearts.

Effects
For each crippled limb you have, you do an additional 10% damage. The damage to limbs must be 100% for the particular perk stages to kick in. Keep in mind that penalties for broken limbs can be completely negated, giving you effectively a huge bonus to damage at no cost at all:

1) Breaking both legs gives you +20% to overall damage at no cost unless you need to move around in a fight (penalty: movement speed decrease)

2) Breaking your eyes (Perception condition) by 100% reduces your perception by 4, which can be negated by using various drugs that increase perception (Absinthe, Coyote Tobacco, Mentats, Party Time Mentats), and applies a visual "Concussion" effect, which may obfuscate your view in a fight, but incurs no penalty in VATS mode (provided you counter the PER penalty as noted above).

3) Breaking your left arm incurs no penalty to HIT chance in VATS if you are using a single-handed weapon. However, never break your right arm or any arm if you are relying on a rifle, because the chance to hit in VATS is decreased by a huge amount (down from 95% to appr. 20%), so breaking your arms (or at least your right arm if relying on a pistol) is not recommended. As such, the overall realistic damage bonus you get from this perk is 30% for rifles and 40% for pistols.

It is possible to trigger this perk through the in-game console by typing the following:

1) player.damageav perceptioncondition 100

2) player.damageav leftmobilitycondition 100

3) player.damageav rightmobilitycondition 100

4) player.damageav leftattackcondition 100 (left hand, not recommended for rifles)

5) player.damageav rightattackcondition 100 (right hand, not recommended, see above)

Behind the Scenes

 * It is possibly a reference to the Bible passage Exodus 21:24, "Eye for an eye, tooth for a tooth, hand for a hand, foot for a foot".
 * The name of this perk might also be a reference to Hammurabi's Code, a law system developed by the Mesopotamian king, Hammurabi, where a peasant would receive a punishment equal to the crime they committed.
 * It should be noted that the perk says Eye for Eye, instead of the more correct way of saying it, an eye for an eye.