Regeneration (3.5e Feat)
From D&D Wiki
After every round of combat, roll 1d6 and recover that many health points. Can only recover HP if you roll a Fortitude Save DC 15. If stacked then add 5 more to the DC. so after stacking after the first time then the DC is 20.
Prerequisite: Con 15, Base Fortitude +7
Benefit: Gain HP
Normal: Normally a character would have to be a cleric to heal themselves, but this can be use to recover no matter what race or class you are.
Special: This Feat can stack so every time you take it you gain 1d6 to the original roll