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Authoring system
Link Download
Developer Sean Ellis
Format Other
Interaction style Parser
System Atari ST
System details
Latest version
Status Stable
Uses interpreter
Multimedia support sound, graphics, loading screen
License Former Commercial
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STAC is an authoring system for the Atari ST that was released in 1988 by Incentive Software. STAC is short for Atari ST Adventure Creator.

The STAC was a 16-bit evolution of Sean Ellis' original 8-bit GAC system, that was popular on machines like the Amstrad CPC and ZX Spectrum. A version of STAC for the Amiga was planned but never completed.

The system was sold on two discs which included the STAC tool, a demonstration adventure, a collection of fonts, sample adventure screens, a full adventure game made with STAC (The Case of the Mixed-Up Shymer) and an extensive 70-page manual.

The system was relatively expensive. It sold in the UK for £39.95. In the US it was released by Terrific Software for $69.95. It was distributed in Italy by Atari Italia.

Over 80 adventures were produced and released using the system. They were mostly distributed as shareware and public domain software with relatively few sold commercially.


The packaging for the system lists the main features as follows:

  • Graphic Editor/Designer - includes import feature
  • Character Font Editor
  • LINK feature enables adventures of unlimited size to be created
  • Oops ability
  • Test adventure within STAC
  • Over 120 different conditional actions
  • No licence fee to pay
  • Loading screen option
  • Music in messages
  • Advanced Parser - that can also accept and handle String Inputs
  • RAM/Save and load features
  • Hundreds of flags and counters
  • Synonym recognition
  • 40 and 80 column text under player control. Change from with STAC and the adventure
  • Print text anywhere even over graphics
  • Printer options etc. etc. etc.
  • East to use, powerful and flexible


The games will only run from drive A: unless the .PRG file is patched. However, the STAC engine wasn't geared up for games compiled with it to run from a hard-drive due to it's use of the file-selector when saving/loading a game.



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