Hibernate

(Dragon Compendium, page , DnD 3.5)

[General]

When you sleep, you heal at an increased rate.

Prerequisite

Endurance, CON 13

Benefit

So long as you get at least 8 hours of uninterrupted sleep, you regain hit points equal to twice your character level and heal 2 points of ability damage to each ability score. If you sleep uninterrupted for a full 24 hours, you regain hit points equal to four times your character level and heal 4 points of ability damage to each ability score. "Uninterrupted sleep" does not need to take place in a bed.

Normal

When you rest a full 8 hours, you regain hit points equal to your character level and heal 1 point of ability damage to each affected score. If you have complete bed rest for a full day and night, you regain hit points equal to twice your character level and heal 2 points of ability damage to each affected score.