Pit Fighter (3.5e Feat)
From D&D Wiki
 Pit Fighter [Archetype]
You were born as a slave; not to serve, but to fight. Or you're just a battle freak, fighting as a gladiator as a pastime.
Prerequisite: Bab +1, 1st level character.
Benefit: See below
Special: If you ever stop qualifying for this feat, you can trade it for another archetype feat that you meet the prerequisites for.
Archetype Feat Bonuses are based on HD.
- 1 HD: You gain 4 extra HP, and gain one additional hp per level thereafter.
- 3 HD: You are immune to fatigue, and anything that would cause you to become exhausted makes you fatigued instead.
- 8 HD: The Pit made you much much more resilien;, you can now shrug of most of your opponent's blows (and the stones the spectators throw at you). You gain Damage Reduction 3/-.
- 15 HD: You are a nearly invincible machine of combat, you gain immunity to stunning, critical hits, ability damages and ability drain.