Used Unreal Tournament 2004 RPG Mutator for Windows?
Developer’s Description
By Mysterial
Use this mutator to gain experience points as you frag your enemies.
This mutator adds an RPG element to Unreal Tournament 2004. As you frag enemies you get experience points, and once you accumulate a certain number of points you gain a level. As you gain levels you are awarded stat points that you can apply to stats such as weapon speed, starting health, max ammo or any number of the 21 special abilities available.