Longevity

 is a hero trait.

Mechanics
The hero's randomly determined lifespan is 125% of normal. The mean lifespan for heroes is 65 years, so the mean lifespan for heroes with this trait is 81.25 years.

This stacks through multiplication with other lifespan modifiers. For example, the lifespan for a hero with Health-Conscious and Longevity is 156.25% of normal, bringing the mean lifespan to about 102 years.