Level Editing involves defining and creating interactive architecture for a segment of a game, including the landscape, buildings and objects.

Level editors must be true to the overall design specification, using the characters and story elements defined during the Game Design process, but they often have considerable freedom to vary the specific look and feel of the level for which they are responsible. They define the environment, general layout of the spaces within the level, and lighting, textures, and forms. They define the characters and objects involved, whether they are player-controlled or non-player characters, and any specific behaviours associated with the characters and objects.

They also develop the gameplay for the level, which includes the challenges that the characters face and the actions they must take to overcome them. The architecture helps to define those challenges by presenting obstacles, places to hide, tests of skill, and other elements to explore and interact with.

The setting and atmosphere devised by the Level Editor can also give the player clues about different ways of progressing though the level and the game as a whol

The Level Editor first sketches ideas on paper or using 2D drawing software. They have to imagine the playing experience, putting themselves in the position of the player, mapping out all the possibilities.

The ideas are then worked out in 3D and tested in the game engine, which produces further ideas. In consultation with the Programmers and Artists, the Level Editor draws up a detailed inventory of level ‘assets’ (all the objects and programming requirements needed to make the level run in the game in its final form).

Every asset can impact on the game’s performance and the Level Editor must understand the technical constraints to which the team is working, e.g. there may be a limit on the number and complexity of objects that can be displayed on screen at any one time.