Altitude Adaptation( Secrets of Sarlona, p. 114)
Your body adapts quickly to changes in altitude, preventÂing you from suffering as much from altitude sickness.Prerequisite
Base Fortitude save +2,
You gain a +4 bonus on Fortitude saving throws to avoid the effects of altitude (DMG 90). AddiÂtionally, when you determine what effect the altitude has on you, you apply the effect for the next lower category of altitude than the category you are actually in. After you spend a week at a specific altitude, you become acclimated to that altitude and all lower altitudes, and no longer have to make Fortitude saves for each 6-hour period to avoid altitude sickness. If you travel to a lower altitude and remain there for a week, you lose your acclimation to the higher altitude and must reacclimatize, although you always retain the other benefits granted by this feat.Special
This feat grants a +2 bonus on Survival checks made in high altitude (above 5,000 feet) areas.