Enhanced PC Speaker supportZeliard had a unique PC Speaker support: It could play music with multiple channels. To activate this, you had to install the game with PC Speaker as the music device. When running the game, use the F1 key to toggle between the following modes:
- Music On; Single Channel
- Music Off
- Music On; Multiple Channels
- Music Off
GraphicsWhen using EGA the game's resolution is 640x200 instead of 320x200. However, MCGA mode uses 64 colors, whereas the EGA version simulates 64 colors by dithering.
MapIncluded with the game was a large poster containing a map of each cavern. While not necessary for gameplay, later levels became quite difficult without it. The map is not quite complete, and omits invisible barriers and doesn't indicate where a door will lead.
Music & soundA nice feature included (which was still somewhat uncommon at the time) is the ability to select different hardware for music and sound effects. Since sound effects are not supported for the Roland MT-32 (only music), this allows a Roland MT-32 to be used for music, and another supported sound device (such as Adlib or Tandy 3-voice) to be used for the sound effects providing an impressive soundtrack.
ProgrammingZeliard was able to have a fairly large smoothly scrolling screen, even on slower computers. This was accomplished by breaking the screen up into a grid, and only redrawing sections that actually changed instead of having to redraw the entire screen for each frame. Sierra used this technique on several other Game Arts conversions, such as Firehawk.
Information also contributed by Servo