A couple of years ago, the first real competitor to The Quill appeared, Incentive's Graphic Adventure Creator, otherwise known as the GAC. The GAC started life on the Amstrad, and soon migrated to both Commodore 64 and Spectrum. By now the Quill was offering add-ons, and eventually PAW, and the GAC failed to displace it amongst those who used it to write adventures for commercial publication.

But the GAC found a great following among adventure enthusiasts seeking to write their own games, and its success was almost certainly due to its extreme ease of use.

Now GAC has become STAC, an adventure creator for the Atari ST, written by GAC's originator, Sean Ellis. But it is far more than just a conversion from the 8-bit formats. Its many advanced features make it an extremely flexible utility, capable of producing adventures that may be difficult to recognise as STACed.

A similar menu-entry system to GAC is used, whereby, in general, the initial letter of the option required is hit to enter it. Type R, for example, and you are immediately into Room descriptions, displayed as a single screen form. Connections with other rooms, and long and short text fields are entered here - press RETURN and you move on to the next input field, with a final 'Y or N' to keep or abort the entry if you have made a mess of it.

The graphics option is a superb utility for drawing pictures (I had a great deal of fun with it) and offers sixteen colours on the same screen. These can be set to any shade you want simply by sliding three little boxes up and down against a scale, until you get the exact mix that suits you. Pictures produced using Neochrome and Degas can also be used in the adventure.

The text, too, has its graphics side! A Font option allows you to design your own lettering style within an enlarged box broken down into magnified pixels.

All this, and sound too! As well as bleeps and buzzes, music can be incorporated into a message. Chords can be played, although being a single channel, it would be extremely difficult to write a tune with a true accompaniment, and the volume of all notes played will be the same.

Other features offered by STAC are: string manipulation facilities, computations within conditions, and the linking of disks, so that adventures spanning more than one disk may be produced.

With the package comes a 68-page manual, plus a free copy of Shymer, an adventure written by Sheila Sharkey - but this time is is fully illustrated, with some really stunning pictures.

There is but one disappointment in the package - although you can change the textsize, the program cannot be used with a mono monitor.

With the STAC, GAC has come of age, in the same year as its author Sean Ellis, now 21, and a graduate in Cybernetics and Computer Science.

Will we soon see an even more advanced AMAC?