Hot Blooded

"When your health drops below 50% you gain +10% more damage, but you also suffer -2 to your Agility and Perception attributes."

- Fallout: New Vegas description

Hot Blooded is a trait in the Fallout: New Vegas add-on Old World Blues.

Effect
When your health drops below 50% you deal +15% more damage (see Bugs below), but you also suffer -2 to Perception and Agility.

Bugs
Although the trait description claims the bonus is 10%, it is actually 15%, making this trait even more useful.