level designer
A level designer is a person who creates levels, challenges or missions for computer and video games using a specific set of programs. These programs may be commonly available commercial 3D or 2D design programs, or specially designed and tailored level editors made for a specific game.
A level designer may also be called a mapper
A level designer needs to have great knowledge about games and how people play them. Bad level design can easily ruin a potentially great game. You main job is to create the game world based on the design document and the graphics provide by the 3D artists. You should be familiar with working with 3D tools and level editors. A lot of people who work with level design started off making mods for existing games as a hobby. Alto of today’s PC games comes with tools and editors that let the player modify the original game and upload these to the internet so other people can play them. These new games are called mods and there is a big community of people making mods of popular PC games today. Counter Strike started out as a Half Life mod and is today one of the most played games in the world. So our best advice if you want to work as a level designer is to get active in the mod community, it will give you the experience and practice need for taking on this position