Setting to enable/disable 3D rendering. 3D rendering makes tiles 3D (cubes instead of squares) and gives sprites a height level.
Note: The 3D rendering mode has been introduced with CS2D 184.108.40.206. All maps can be rendered in 3D but some might look weird. This depends on how they are designed. Especially older maps which have not been designed with the 3D mode in mind might not look right in 3D mode.
Note: 3D rendering can lead to disadvantages in gameplay because some players/items - which are visible in 2D - might be covered by 3D tiles depending on your relative position to them.