- Stamina: Improves by running, swimming, and cycling. Affects how long you can sprint or swim.
- Shooting: Improves by hitting targets, headshots, and completing shooting range challenges. Affects accuracy, recoil, and ammo capacity.
- Strength: Improves by fighting, playing sports (tennis, golf), and punching pedestrians. Affects melee damage, climbing speed, and fall damage resistance.
- Stealth: Improves by moving in stealth mode (crouching). Affects how quietly you move and how long you can remain undetected.
- Flying: Improves by flying aircraft and completing Flight School lessons. Affects aircraft handling and stability.
- Driving: Improves by driving at high speeds, performing stunts, and avoiding collisions. Affects vehicle control and handling.
- Lung Capacity: Improves by swimming underwater. Affects how long you can stay submerged.
Actively engaging in activities that utilize these skills will naturally improve them over time, making your characters more capable.