Mountaineer

You gain a +2 bonus on Climb checks on natural stone surfaces and a +4 bonus on Fortitude saves to avoid high-altitude fatigue and altitude sickness. If you spend 24 hours at a dangerous altitude, you treat that altitude as if it were one category lower. If you spend at least 1 week at that altitude, you are immune to altitude fatigue or sickness. If you go to a lower altitude for more than 1 week, you lose this acclimation.