Sky

You have webbing under your arms, some form of wings or perhaps a mechanical contraption that expands as an action for 1 Stamina. Once expanded, you can glide, falling 5 feet for every 30 feet you travel. If there are strong winds, you can glide without falling, essentially just fly. You can also use this to slow your fall, preventing you from taking falling damage. You can retract your wings at any time as a free action.

When you reach Tier III, you can spend 2 Stamina each turn to gain a fly speed equal to your speed.