Toughness(KJD)

Toughness [Martial]
You have a greater ability to absorb damage.
Benefit: You gain +1 hit point per hit die. When you gain more hit dice, you gain an additional +1 per new hit die.

In a campaign that does not give a fixed number of hit points per hit die, this may instead bump the size of the effective hit die. For example, a Cleric (d8 HD) would instead roll d10 hit points for each level.
Special: You can take this feat more than once. Its effects stack.
Notes: This replaces the Revised System Resource Document Toughness feat.

I didn't like the way core Toughness failed to scale with level. It's a half-decent feat at first level when hit points are at a premium, but a few levels later is typically a wasted feat -- 3 hit points don't much matter when you've got 80. I changed the feat so it instead gave a bonus that scaled with level.