Stamina - How long your character can run, swim or cycle at full speed before losing health due to over-exertion. Increase by practicing any of these skills.
Shooting - Your characters skill in handling various firearms. Dampens recoil, reduces reload times, and increases ammo capacity. Increase by landing hits on enemies, scoring headshots, and successfully completing shooting range challenges.
Strength - Your character's physical power and resilience. Boosts melee damage, speeds up ladder climbing, improves sporting ability, and reduces damage taken from various sources. Increase by scoring hits in melee combat and practicing sports.
Stealth - Your character's skill at remaining undetected. Move more quickly and quietly while in stealth mode. Increase by remaining undetected while in stealth mode and performing silent takedowns.
Flying - Your character's skill in the cockpit of various aircraft. Take off, land, and manage turbulence more easily. Increase by flying under control for sustained periods and succeeding at Flight School challenges.
Driving - Your character's skill behind the wheel or handlebars. Pop wheelies more easily and retain more control while airborne. Increase by holding wheelies and landing squarely out of big jumps.
Lung Capacity - How long your character can hold their breath before losing health. Remain submerged for longer. Increase by diving and swimming underwater.