I found the source code for this on an Atari site that has archived a whole bunch of published materials for early 8-bit computers. There seems to be something about the Atari crowd that inclines them to programming activities. Their collective efforts to support this inclination are also helpful for the rest of us 8-biters. One interesting book they have maintained in digital form is Tim Hartnell's classic Creating Adventure Games on Your Computer. In the course of porting "Chateau Gaillard" to the TRS-80 MC-10, I found a few errors in the original listing. For example, the way the code originally worked the weapon you chose seemed to have no effect on combat. There were elaborate routines for reporting and selecting which weapon you would use, but when it came right down to it, the value entered was not used in the combat routine. There were also some other bugs, such as the interaction with the Dwarf (misreported the objects he was willing to accept during negotiations) and the fact that you could simply "go up" back to the surface from the initial room you fall into, contrary to the message that "there is now no way back." On the whole, the combat routine just seemed overly punishing and I found the game difficult to complete, so I adjusted it. Also, when you moved an excessive number of points were randomly subtracted from your statistics. I changed it so that only your strength is randomly diminished as you explore, and at a much lower rate. Now you at least have a chance of finding the healing potion and replenishing your strength. I also added a routine to allow you to re-roll your character stats at the beginning of the game until you get a reasonably fair dispersal. As with most Basic two-word parsers there are some quirks. There is no shorthand N, S, E, or W for moving. The closest you can get is GO N, GO S, etc. Otherwise, three letters is all you need for either word to register. However, I added a single word "INVENTORY" command, because I didn’t like seeing an inventory automatically with every new screen. There are lots of arbitrary deaths in this game from traps, so you’ll just have to play it multiple times and map it enough to learn where not to go. That being said, some meager clues are given to help you avoid some of these deaths. The basic object of the game is to find the two keys, which are needed to allow you to escape two rooms that otherwise lock you in. Once you get the right keys for the right rooms, you can use them to unlock all the doors in those rooms, which will allow you to find a stairwell back to the surface. On the whole, it is a fun little 8-bit Basic dungeon romp. The combat routine is quite unique in the way it allows you to choose which vital statistics you will draw on in your combat against the different creatures (which have some very creative names) and their distinctive vital stats. In brief you should try to select your highest stats while selecting the lowest equivalent stats of your opponent. Various clues about how to overcome dangers are also sprinkled throughout the maze, which is a nice touch. If you get stuck there is a map below to give you a hand. The coordinated colors indicate various rooms with ways to move up or down between the levels.
** SPOILER ALERT **