Nitfol

Nitfol, along with frotz, is one of the most popular z-machine interpreters and debuggers for infocom and inform interactive fiction games. It makes use of the glk API, and supports versions 1 through 8 of the z-machine, including the version 6 graphical z-machine. Save files are stored in the standard Quetzal save format. Binary files are currently available for several different operating systems, including Macintosh, Linux, MS-DOS, and Windows.

Nitfol's features include Unlimited undo and redo, typo-correction, automatic map generation, aliases, and an extensive set of options.