race features:
On Fiendish Wings. You have bat-like wings that can sprout from your shoulder blades or disappear back into your body instantly, at-will. You have a flying speed of 30 feet when in combat (or any other situation your DM determines requires sufficient focus), or a flying speed of 40 feet outside of those situations--such as during overland movement. You can’t use this fly speed if you are wearing medium or heavy armor or are heavily encumbered.
Hellish Regeneration. Given food, water and a bit of proper rest, your kind can recuperate from the most grievous of wounds. When regaining hit points for resting, assume your hit dice roll the highest results. If you lose a body part, it will regrow and return to full functionality after 1D6 + 1 days if you maintain at least 1 hit point for the duration