Starspawn( Lords of Madness, p. 181)
Your abnormal body and heritage has become more pronounced. You grow membranous wings and are comfortable in extreme elevations.
Aberration Blood (LoM) , one other aberrant feat,
You gain a fl y speed (with average maneuverability) equal to one-half your base land speed (round down to the nearest 5-foot increment). You can use your fl ight for a number of consecutive rounds equal to 1 + your Constitution modifi er (minimum 1 round); between these uses you cannot fl y for 1 round. You gain resistance to cold 5. You are immune to altitude fatigue and altitude sickness.