This is a list of various new features introduced in the Mapster32 map editor, purely for the sake of those who have never used Build and are curious about the differences. It is by no means complete, I just add things as I notice them. I have particularly excluded many of the new keypresses from this list, since they are already documented in their own section. The superannuation of Build has clouded my recollections of what exactly are 'new' features, which explains why so many are probably missing. There are many features that I realize are new, yet I can't imagine having ever mapped without them.

• Many annoying or even destructive bugs have been fixed.
• Z co-ordinate 'float mode' is enabled by default.
• Walls with one-sided blocking enabled appear as green, as do most sprites (provided they are unblocked).
• The 10 intangible special sprites appear as white, enemies/babes appear as orange, and weapons/ammo/health/inventory appear as blue.
• Various map corruption prevention features are present. Completely collapsing red-lined sectors is no longer possible, and attempting to join non-adjacent sectors displays a warning prompt.
• Texture display modes in 2D mode can be cycled through with Backspace (very cool).
• The option of 'first wall' highlighting with F4 (in 2D mode). The first wall of a highlighted sector will appear as yellow.
• The player start position arrow has changed from brown to green.
• There are various other colour scheme changes, such as vertices being white.
• There are half-point markers on walls, as well as real-time wall measurement displays while moving vertices.
• Wall-aligned sprites display as a line, and floor-aligned sprites display as a box. Both represent their actual dimensions.
• Walls which exceed their length limits are displayed as blue as a visual warning.
• The ability to directly edit object attributes in 2D mode with F7 (for sectors) and F8 (for walls/sprites).
• An improved search feature with Alt + F7 (for sectors) and Alt + F8 (for walls/sprites).
• Textures are organized into 'tilesets': Press T while browsing the standard texture selection menu (V) to access the predefined tilesets. These are even configurable within tiles.cfg.
• MusicAndSFX sprites display a circular perimeter indicative of their AudibleRadius (Hi-Tag) value.
• Ambient sounds can be heard in 3D mode. This can be toggled with F4 (in 3D mode).
• Definition names are displayed as you enter tag values (i.e. SectorEffector Lo-Tag function names and MusicAndSFX Lo-Tag sound effect names).
• The 2D mode menu display has been minimized, allowing for a larger field of vision.
• A fancier font style has been implemented.
• The size of the mapping grid is customizable.
• The number of map corruption errors (if any) will be displayed in the top left corner.
• The ability to move copied sprites together as a unit, and the ability to copy several independent objects at once.
• The "smart-tagging" feature allows you to assign channel values via custom labels (for example, "switch1"), which will then be automatically converted to unique numerical values.